New options: vimrplugin_compldir and vimrplugin_tmpdir
- Move files created by R for omni completion and syntax highlight of R
  functions to $AppData in Windows and to ~/.cache/Vim-R-plugin in Linux, and
  let users change these directories paths.

- Fix bug: omnicompletion was not working when the library has their omnls_
  and fun_ files written for the first time.

- Avoid E341 (Internal error: lalloc(0, )) in a more efficient way.
libvimcom.so was renamed libVimR.so
Fix ReadEvalReply(): use old code.
Merge remote-tracking branch 'upstream/master'
Replace rplugin_esc_tmpdir with rplugin_tmpdir
Call BuildOmniList() in the first run of CompleteR()
Can't run `syntax enable`
Highlighting defined in the vimrc is lost after `syntax enable`.
Merge remote-tracking branch 'upstream/master'
Use BufEnter event to update syntax
Also fix mistake in the use of len() function.
Wait for \ao to finish in Neovim too
I have made an attempt of avoiding Neovim freezing while R CMD BATCH was
running, but if the user was typing something when R finished, the last
typed keys would go to the new tab. Vim has the function feedkeys(), but
in this case we need the opposite, whose name could be consumekeys().
Merge remote-tracking branch 'upstream/master'
Make sure RCheckLibList() exists

Prevent error messages for non R filetypes
Merge pull request #149 from mdlerch/rcheckliblist_exists

Make sure RCheckLibList() exists
Set rplugin_uservimfiles in setcompldir.vim
~/Library/Caches/Vim-R-plugin as OS X cache dir
Try iTerm and Terminal full paths on OS X
Require vimcom 1.1-15.
Delete no longer required objlist/README
Replace vimrplugin_external_ob with _tmux_ob
Update documentation