LGPL Library Split

[beserge]

What this does

• Moves all LGPL licensed modules DaisySP to a new submodule repository DaisySP-LGPL.
• After updating libDaisy, and DaisySP (including pulling the new submodule), users can add USE_DAISYSP_LGPL=1 to their Makefile, and continue without any other changes.
• DaisySP will stay under the MIT license, DaisySP-LGPL will be under the LGPL license.
• Creates a new module called OnePole ported from pichenettes' stmlib/dsp/filter.h.
  • Necessary to replace the Tone filter in KarplusString without using LGPL code in the MIT codebase. Plus it's a nice module to have around.

TODO

• The existing gh-pages docs will be temporarily split into two. The LGPL modules will have their own gh-pages for the time being.
  • I'm planning on spinning up a mkdocs site like what we have for libDaisy. At that point the LGPL docs will return.

The Modules

• Control/line
• Dynamics/balance
• Dynamics/Compressor
• Effects/bitcrush
• Effects/fold
• Filters/Allpass
• Filters/Atone
• Filters/Biquad
• Filters/Comb
• Filters/Mode
• Filters/moogladder
• Filters/NlFilt
• Filters/Tone
• PhysicalModelingpluck
• PhysicalModelingpolypluck
• Synthesis/blosc
• Utility/jitter
• Utility/port