Automatic merge of T1.5.1-981-g27e5ffb7b and 17 pull requests

- Pull request #799 at dfc715e: Consolidated wind simulation
- Pull request #839 at d00beb9: First phase of https://blueprints.launchpad.net/or/+spec/additional-cruise-control-parameters
- Pull request #876 at f92de76: docs: add source for documents previously on website to source Documentation folder
- Pull request #882 at b3f83ed: Blueprint/train car operations UI window
- Pull request #885 at 56c17fb: feat: Add notifications to Menu
- Pull request #891 at 9a1d6b2: Auto save
- Pull request #892 at 1f5ba4c: Signal Function OPP_SIG_ID_TRAINPATH
- Pull request #896 at 5866028: First implementation of https://blueprints.launchpad.net/or/+spec/specific-sounds-for-ai-trains
- Pull request #900 at c27f32d: DMI updates
- Pull request #903 at 3e390b8: Downloading route content (Github, zip)
- Pull request #912 at cda1d74: New Triple Valve Features Vol. 2
- Pull request #922 at abe2e52: Autopilot for timetable mode
- Pull request #943 at fb1f454: Dynamic Brakes Behavior & Display Improvements
- Pull request #946 at 66f836c: Advanced track sounds
- Pull request #948 at a687981: Fix Cycling Lights
- Pull request #949 at c2a5d32: Oil Burning Locomotive
- Pull request #950 at a98ff62: Ctrl-F5 showing yellow rectangles where mouse left button is active

Author: openrails-bot