Don't set global options

[garious]

Per Sergey Dmitrouk:

Unfortunately, just moving files around isn't enough. Sample vimrc
can't be turned into a plugin that easily. The problem with such setup is
that plugin sets global options and even runs set nocompatible, which
silently resets a bunch of options even if 'compatible' is already "off".

The proper way of doing this would be factoring that file into smaller
ones (filetype detection plugin, filetype plugin) and ensuring that options
that are left in the plugin affect only buffers of LLVM tree (by using
:setlocal and matching file path or requiring secondary file type like in
"cpp.llvm").