Exposes the raw LV2 interface (C language) to Rust

LV2 docs: http://lv2plug.in/

The documentation of this crate is copied from the original C files, whose copyright holders include Steve Harris, Lars Luthman, Gabriel M. Beddingfield, David Robillard, Richard W.E. Furse, Paul Barton-Davis, Stefan Westerfeld, and possibly others.

Note

The objective of this crate is to translate the C interface as closely as possible to Rust, declaring e.g.

• type aliases for raw pointers
• [repr(C)] structs
• extern "C" fn declarations passed to the host in the LV2Descriptor struct

The original (C language) LV2 package defines contains some "helper" functions, which are defined in C-headers, i.e. there is no compiled library file which this crate could link to. These functions are also declared and defined here. Let us know if you think that's not right. See also this question on stackoverflow.

The lv2 crate is one attempt to provide a more idiomatic Rust interface to LV2.

Roadmap:

• Figure out division line between low- and high-level crate
  • Preliminary goal: provide all functionality of LV2 while keeping it low-level
• Find out how much abstraction is useful/affordable in audio applications (i.e. real-time).