Adds wallhacks

[ixil]

Just hacking/procastinating, does good enough for my usecase, so ymmv. New variable set to: g:qs_augrp_clean = ['EasyMotionPromptBegin']

For example usage: nmap f <Plug>(QuickScopeWallHacksF)<Plug>(easmotion-fl). It's not perfect but it helps.

As a follow up to pr-71 and may help with issue [#55].

You probably don't want to merge until some others have tried this out.