Remove donation value from backers.md
Sort backers.md
Add some missing backers and remove duplicates
Move functions from os/fs.c into path.c

Move unit tests from os/fs.moon to path.moon
Move and adapt `os_get_absolute_path` unit tests to `vim_FullName`

* Add two new unit tests to `vim_FullName`
* Make `os_get_absolute_path` static
Change prefix from `os_*` to `path_*`
Move exe functions back to os/fs.c
vim-patch:7.4.186

Problem:    Insert in Visual mode sometimes gives incorrect results.
            (Dominique Pelle)
Solution:   Remember the original insert start position. (Christian Brabandt,
            Dominique Pelle)

https://code.google.com/p/vim/source/detail?r=4d12112c5efae071aecbeed1a7196f18950457b3
Fix broken build due to unit test include order

 Commit 4348d1e6f74a87af55c6c01e7a0cb292e9dec114
 introduced a bug that breaks the unit tests unless
 they run in a certain order. Both path.moon
 and os/fs.moon tries to include the same Enum, which
 fails since ffi.cdef can only include definitions once.

 This solves the bug by using Lua variables instead of
 ffi.cdef Enums.
Add cmake module for finding msgpack
Configure cmake option to download/install msgpack
Add empty implementations of the remote API
Implement msgpack-rpc helper module

Still missing the `msgpack_rpc_dispatch` function which will be automatically
generated by a script
Add `msgpack_rpc_dispatch`/metadata generator

This adds a lua script which parses the contents of 'api.h'. After the api is
parsed into a metadata table. After that, it will generate:

- A msgpack blob for the metadata table. This msgpack object contains everything
  scripting engines need to generate their own wrappers for the remote API.
- The `msgpack_rpc_dispatch` function, which takes care of validating msgpack
  requests, converting arguments to C types and passing control to the
  appropriate 'api.h' function. The result is then serialized back to msgpack
  and returned to the client.

This approach was used because:

- It automatically modifies `msgpack_rpc_dispatch` to reflect API changes.
- Scripting engines that generate remote call wrappers using the msgpack
  metadata will also adapt automatically to API changes