Fixed neocomplete configuration according to the migration guide

This fixes the [`neocomplete.vim`](https://github.com/Shougo/neocomplete.vim) configuration, that was overlooked in the previous PR, #410. Thanks for the base tho.

Most of the variables were just replaced according to the [migration guide](https://github.com/Shougo/neocomplete.vim/wiki/neocomplete-migration-guide), which have been worked a lot lately. It decreased the amount of required work significantly. These two methods were removed, `g:neocomplete_enable_camel_case_completion` and `g:neocomplete_enable_underbar_completion`, from `neocomplete` and those are just removed here too. I'm not sure if there are some settings that should be used to set similar functionality, so I'm just ignoring those.

Also, `neocomplete` might provide additional functionality when compared to `neocomplcache`, those settings are not yet set. If you have more insight to `neocomplete`, please review the settings, because I'm not even a beginner for that matter.