Instead of using automodule, only document public api functions

Author: kotfu

docs/api/utils.rst

@@ -1,5 +1,78 @@
 cmd2.utils
 ==========
 
-.. automodule:: cmd2.utils
+
+Settings
+--------
+
+.. autoclass:: cmd2.utils.Settable
+    :members:
+
+    .. automethod:: __init__
+
+
+Quote Handling
+--------------
+
+.. autofunction:: cmd2.utils.is_quoted
+
+.. autofunction:: cmd2.utils.quote_string
+
+.. autofunction:: cmd2.utils.quote_string_if_needed
+
+.. autofunction:: cmd2.utils.strip_quotes
+
+
+IO Handling
+-----------
+
+.. autoclass:: cmd2.utils.StdSim
+    :members:
+
+.. autoclass:: cmd2.utils.ByteBuf
     :members:
+
+.. autoclass:: cmd2.utils.ProcReader
+    :members:
+
+
+Tab Completion
+--------------
+
+.. autoclass:: cmd2.utils.CompletionError
+    :members:
+
+.. autofunction:: cmd2.utils.remove_duplicates
+
+.. autofunction:: cmd2.utils.alphabetical_sort
+
+.. autofunction:: cmd2.utils.natural_sort
+
+.. autofunction:: cmd2.utils.basic_complete
+
+
+Text Alignment
+--------------
+
+.. autoclass:: cmd2.utils.TextAlignment
+    :members:
+
+.. autofunction:: cmd2.utils.align_text
+
+.. autofunction:: cmd2.utils.align_left
+
+.. autofunction:: cmd2.utils.align_right
+
+.. autofunction:: cmd2.utils.align_center
+
+.. autofunction:: cmd2.utils.truncate_line
+
+
+Miscellaneous
+-------------
+
+.. autofunction:: cmd2.utils.str_to_bool
+
+.. autofunction:: cmd2.utils.namedtuple_with_defaults
+
+.. autofunction:: cmd2.utils.categorize