Smooth Default Linux Build and Install

[mfisher31]

Required

• Smooth Default Linux Build for Packagers. CMake build without updater compiles cleanly, installs Binaries, Lua Docs, README, and License File (s)
• Use CMake FetchContent instead of submodules.
• Don't use LVTK (just copy a few headers and re-namespace them, convert to camel case)

Optional

If these can't be done in a reasonable amount of time, shelve them for a future release.

• Use System Lua, if available
• Use System JUCE, if available
• Use System Sol3, if available