Don't try to complete included files

Also no need to just repeat the defaults, and `t` and `]` are the
same...
Speed up ctrl-p buffer searches
s/airline/lightline/
Trying for speedup

Somehow I'm not understanding the docs for ttimoutlen and timeoutlen so
it's time to experiment
Back to default 20% split below
No plans to go back to CommandT
Back to defaults for autornu