add hint about modifying files considered as being at risk

Change-Id: I6ad9c682697e80e175cb19d67d3167c1756cd311
Reviewed-by: Orgad Shaneh <orgads@gmail.com>
Reviewed-by: Oswald Buddenhagen <oswald.buddenhagen@theqtcompany.com>
exclude plist files from the eol-at-eof check

xcode always omits it.

Change-Id: I37b1e799d08d595aee4c227f9ed7af3eca69a6b8
Reviewed-by: Orgad Shaneh <orgads@gmail.com>