Almost all synthesizer code in Piano is removed in favor of the LibDSP
reimplementation.
This causes some issues that mainly have to do with the way Piano
currently handles talking to LibDSP. Additionally, the sampler is gone
for now and will be reintroduced with future work.
SPDX License Identifiers are a more compact / standardized
way of representing file license information.
See: https://spdx.dev/resources/use/#identifiers
This was done with the `ambr` search and replace tool.
ambr --no-parent-ignore --key-from-file --rep-from-file key.txt rep.txt *
