fixed typo, purely cosmetic

"executable" was written as "exectuble" and "exectuable"
Merge pull request #721 from SpiritQuaddicted/patch-1

fixed typo, purely cosmetic
remove related pid file when kill the controlled process among seafile-controller
modify commited code format
change indent of commited code
Merge branch 'master' of github.com:jyelee/seafile