Added mount cheatsheet
Added git cheats
cheat awk: sum integers from a file or stdin
Merge pull request #40 from carlosp420/master

cheat awk: sum integers from a file or stdin
Merge branch 'master' of https://github.com/ozdemircili/cheat into ozdemircili-master

* 'master' of https://github.com/ozdemircili/cheat:
  Added git cheats
  Added mount cheatsheet
Minor changes to the git cheatsheet.
Trivial change to mount cheatsheet.