Renderer improvements

[jaihysc]

Optimize renderer

• Render tiles via tessellation
• Remove need for alpha test
• Reduce waiting in render threads
• Avoid rendering unseen tiles
• Remove virtual calls when rendering
• Force inline hot paths
• Switch to contiguous container of ids, read by renderer

Improvements

• Can zoom further in, further out
• Move sprite processing to be done at startup
• Add startup check for incorrect sprite group (Avoids runtime errors)
• Improve inserter arm aesthetics
• Use Freetype for font rasterization
• Move faster when zoomed further out
• Sped up chunk generation
• Log level can be changed at runtime
• The test/ subdirectory is no longer included, only for test build

Bugfixes

• Fix inserter crash after save + reload
• Fix incorrect mining drill output on conveyor after save + reload
• Fix assert failure when mining drill has an output built, but has no resources
• Fix unable to click gui buttons when holding item