OpenBVE v1.9.1.1

As always, a new release seems to bring some new and interesting bugs, as well as locating older ones :( This release should fix OpenBVE failing to start on systems requiring the GL3 menu (Primarily newer versions of OS-X)

Significant Changes:

• Fix: OpenBVE failed to launch with the GL3 menu due to a train plugin interface change.
• Fix: Incorrect texture caching access for trains with nighttime textures.
• Fix: Issue using the Windscreen section later in a Panel2
• Change: Remove various bits of older BVE2 hacks related code from the PanelXML parser- This should have no effect on user content.