Adds additional crlf clobber avoidance.

Adds the hook-scripts to .gitattributes due to the shell-scripts not
liking CRLF which they will get if a user sets 'autocrlf = true'
in their global gitconfig.

Further, since the python interpreter can handle either CRLF or LF, 
python-scripts specific line-ending rules have been removed.

Change-Id: I2d6bfd491b2f626b9ca93c40a3a7f2cfba6c54f0