Don't derive `Function` from `Clone`
Add doc to gitignore and implement Compile for primitives using compile_prim macro
Remove `i32` cast in Compile implementation for string slices
Add jit macro
Implement some more Iterator methods on dependency iterator
Group unsafe blocks in `context.build`
Make unsafe block in `size_hint` of `Functions` minimaal
Always inline cheap constructors
Include lifetime of context in lifetime parameter
Move `create_struct` and `create_union` implementation to their respective functions
Make `type.get_size()` return a `uint`
Use `#[inline(always)]` for one-liners