Improve package documentations

The first sentence is of special importance as it is used in the Javadoc package list and as such the first thing a user reads about the package. It should be terse and informative.

Author: nicolaiparlog

src/main/java/org/codefx/libfx/collection/transform/package-info.java

@@ -1,6 +1,6 @@
 /**
  * <p>
- * This package contains transforming collections.
+ * Provides transforming collections.
  * </p>
  * <h2>Overview</h2>
  * <p>

src/main/java/org/codefx/libfx/collection/tree/navigate/package-info.java

@@ -1,7 +1,6 @@
 /**
- * This package provides an abstraction to navigate <a
- * href="http://en.wikipedia.org/wiki/Tree_%28data_structure%29">tree</a>-like data structures without requiring them to
- * implement a specific interface.
+ * Provides an abstraction to navigate <a href="http://en.wikipedia.org/wiki/Tree_%28data_structure%29">tree</a>-like
+ * data structures without requiring them to implement a specific interface.
  * <p>
  * It contains the {@link org.codefx.libfx.collection.tree.navigate.TreeNavigator TreeNavigator} interface and several
  * implementations, e.g. for AWT, Swing and JavaFX component hierarchies.

src/main/java/org/codefx/libfx/collection/tree/package-info.java

@@ -1,5 +1,5 @@
 /**
- * This package provides functionality around streaming the elements of <a
+ * Provides the possibility to stream the elements of <a
  * href="http://en.wikipedia.org/wiki/Tree_%28data_structure%29">tree</a>-like data structures.
  * <p>
  * Its main purpose is to enable easy creation of {@link java.util.stream.Stream Stream}s of nodes over tree-like data

src/main/java/org/codefx/libfx/collection/tree/stream/package-info.java

@@ -1,10 +1,10 @@
 /**
- * With {@link org.codefx.libfx.concurrent.when.ExecuteOnceWhen ExecuteOnceWhen} and
- * {@link org.codefx.libfx.concurrent.when.ExecuteAlwaysWhen ExecuteAlwaysWhen} this package provides two classes which
- * help to make sure some action which is triggered by a change on an {@link javafx.beans.value.ObservableValue
- * ObservableValue} gets executed under threading. Refer to the two classes for a detailed description.
+ * Allows to make sure some action which is triggered by a change on an {@link javafx.beans.value.ObservableValue
+ * ObservableValue} gets executed under threading.
  * <p>
- * Instances of those classes can be built with {@link org.codefx.libfx.concurrent.when.ExecuteWhen ExecuteWhen}.
+ * Refer to the two classes {@link org.codefx.libfx.concurrent.when.ExecuteOnceWhen ExecuteOnceWhen} and
+ * {@link org.codefx.libfx.concurrent.when.ExecuteAlwaysWhen ExecuteAlwaysWhen} for a detailed description. Instances of
+ * those classes can be built with {@link org.codefx.libfx.concurrent.when.ExecuteWhen ExecuteWhen}.
  *
  * @see org.codefx.libfx.concurrent.when.ExecuteWhen ExecuteWhen
  */

src/main/java/org/codefx/libfx/concurrent/when/package-info.java

@@ -1,6 +1,6 @@
 /**
- * This package provides functionality around UI Controls. Subpackages might provide additional functionality for
- * existing Swing or JavaFX controls, implement new ones or provide other features related to controls.
+ * Provides functionality around UI Controls. Subpackages might provide additional functionality for existing Swing or
+ * JavaFX controls, implement new ones or provide other features related to controls.
  */
 package org.codefx.libfx.control;
 

src/main/java/org/codefx/libfx/control/package-info.java

@@ -1,8 +1,8 @@
 /**
+ * Makes using a {@link javafx.scene.control.Control Control}'s {@link javafx.scene.control.Control#getProperties()
+ * propertyMap} more convenient.
  * <p>
- * This package provides functionality to make using a {@link javafx.scene.control.Control Control}'s
- * {@link javafx.scene.control.Control#getProperties() propertyMap} easier. As such its main use will be to creators of
- * controls.
+ * As such its main use will be to creators of controls.
  * </p>
  * <h2>Listening to the Property Map</h2>
  * <p>

src/main/java/org/codefx/libfx/control/properties/package-info.java

@@ -1,7 +1,7 @@
 /**
  * <p>
- * This package provides functionality around JavaFX' {@link javafx.scene.web.WebView WebView}. All of it can be
- * accessed via the utility class {@link org.codefx.libfx.control.webview.WebViews WebViews}.
+ * Provides functionality surrounding JavaFX' {@link javafx.scene.web.WebView WebView}. All of it can be accessed via
+ * the utility class {@link org.codefx.libfx.control.webview.WebViews WebViews}.
  * </p>
  * <h2>Hyperlink Listener</h2>
  * <p>

src/main/java/org/codefx/libfx/control/webview/package-info.java

@@ -1,6 +1,6 @@
 /**
  * <p>
- * This package provides functionality around DOM, i.e. classes from {@code org.w3c.dom}.
+ * Provides functionality around DOM, i.e. classes from {@code org.w3c.dom}.
  * </p>
  * <h2>Event Conversion</h2> The class {@link org.codefx.libfx.dom.DomEventConverter DomEventConverter} defines methods
  * which allow the conversion of {@link org.w3c.dom.events.Event DOM Events} to {@link javax.swing.event.HyperlinkEvent

src/main/java/org/codefx/libfx/dom/package-info.java

@@ -1,5 +1,5 @@
 /**
- * This package provides classes which make it easier to add and remove listeners from observable instances.
+ * Provides classes which make it easier to add and remove listeners from observable instances.
  * <p>
  * Using the default JavaFX 8 features, it is necessary to store both the observed instance and the listener if the
  * latter has to be added or removed repeatedly. A {@link org.codefx.libfx.listener.handle.ListenerHandle