v0.3.1 | Alpha release

This is the first publicly available version of the road generator, in a state that we believe other users are safe to try it out under the guise of it being still in alpha. Some things still may change, but this is already a big step forward over completely manual road creation.

See milestone for issue-oriented list of updates:

https://github.com/TheDuckCow/godot-road-generator/milestone/6?closed=1

What's Changed via PRs

• Style update to the show-hide road toolbar. by @TheDuckCow in #71
• Address several issues for release v0.3.1 by @bdog2112 in #76
• 3D Widget undo and redo by @TheDuckCow in #60
• 54 panel undo redo support by @TheDuckCow in #83

Full Changelog: v0.3.0...v0.3.1