Remove more OOM error handling code

From the functions:

 - ExpandBufnames
 - buf_modname()
 - do_autocmd_event()
 - ff_create_stack_element()
 - ff_get_visited_list()
 - ins_complete()
 - msg_show_console_dialog()
 - prt_find_resource()
 - vim_findfile_init()

TODO: refactor msg_show_console_dialog() to make sure it doesn't ever return
NULL.
Remove OOM error handling code after calls to diff_alloc_new()
Remove OOM error handling code after calls to transstr()

transstr() doesn't return NULL anymore.
Remove OOM error handling code after calls to mf_hash_grow()
Remove OOM error handling code after ga_grow() calls
No error condition in foldInsert()
alist_add_list() doesn't return -1 anymore
No error condition in get_arg_list()
No error condition in store_loop_line()
No error condition in push_current_state()
port vim_mkdir, mch_rmdir and mch_remove to libuv
removed mch_remove macro
removed mch_rmdir macro
removed vim_mkdir macro
vim-patch:7.4.192

Problem:    Memory leak when giving E853.
Solution:   Free the argument. (Dominique Pelle)

https://code.google.com/p/vim/source/detail?r=04c4ef8c0a1b757494500e46400552b135135e94
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