An alternative implementation of CtrlPSameName map

Add a (disabled) alternative implementation of CtrlPSameName -- doens't
affect the command and seems to work about the same as feedkeys.
Replace location list jump with quickfix file jump

I don't use location lists much and I'm often jumping between quickfix
files. Require another modifier to use location list marks.
Add args support to bufgrep (ArgGrep)

Added an ArgGrep command that works like BufGrep.
Now the name is dumb. (Although args are buffers, so
I will leave it for now.)
Use ctrlp_default_input for CtrlPSameName

Using ctrlp_default_input doesn't have issues with mappings (since text
goes through a variable). Replace the old versions with this awesome
version.