Disable neocomplcache and supertab.

If want to enable them, you can
(1) set g:neocomplcache_enable_at_startup to 1,
(2) cancel the comment about supertab.

For example,
let g:neocomplcache_enable_at_startup=0
let g:SuperTabDefaultCompletionType='<C-X><C-U>'
let g:SuperTabRetainCompletionType=2