v1.8 release

What's Changed

• Autogenerate documentation PDF by @MrAnno in #70
• docs: fix supported devices table by @MrAnno in #71
• Parser refactor by @norberttak in #72
• GenericScreen: add dataref array type by @norberttak in #73
• Bugfixes by @norberttak in #76
• Xplane sdk 40 update by @norberttak in #78
• move source files into folders by @norberttak in #79
• Error message display by @norberttak in #80
• Lua: call luapop after all lua C calls by @norberttak in #81
• config: add Felis 747-200 sample config by @norberttak in #74
• Version bump for v1.8 by @norberttak in #82

Full Changelog: v1.7...v1.8