Change range of LFO from [-1, 1] to [-0.5, 0.5].

LMMS does this for some reason
Add LFO to triple oscillator
lmms-lv2-import update for LFO addition

However, the script still sucks because RDFlib cannot handle writing Turtle
properly.  The output contains synthesized prefixes with a leading underscore.
The breaks the drobilla toolkit. Just going to do String.format and call it a
day.
Add triple-oscillator presets
Update README. Set default wave to one that works
Do not install test binaries