Get `run_key_action` to export correctly to C

Add a new wrapper function for `run_key_action` that uses C appropriate
inputs & outputs and calls into our Rusty `run_key_action`. This new
function now correctly gets a header generated for it by 'cbindgen'.

Immense thanks to Jake Goulding on the Rust FFI Omnibus for showing me
how to pass a slice argument from C:
http://jakegoulding.com/rust-ffi-omnibus/slice_arguments/

In order to pass the slice from C, we need to pass a C array and its
length to the function. Cool.

1 files changed, 1 insertions, 0 deletions

diff --git a/src/lib.rs b/src/lib.rs
index db113dc..cf7dd1e 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -2,6 +2,7 @@ extern crate cocoa;
 
 #[macro_use]
 extern crate combine;
+extern crate libc;
 
 mod cocoa_bridge;
 mod parser;