Add quotes to filename for spaces and pdftk-1.45

Two changes here, maybe need to be branched.  First and foremost,
add single-quotes to filename so spaces in paths/files are handled.

Second change set incorporates pdftk-1.45 new multi-char handles -
this implementation allows 26^2 handles.  Lastly, rotation changes
from N E S W to north east south west.

http://www.pdflabs.com/docs/pdftk-version-history/
Merge pull request #1 from alexgann/patch-1

Add quotes to filename for spaces and pdftk-1.45 multi-char handles, direction name changes