[PATCH v3 0/3] cat-file: add "--literally" option

Third version of the patch submitted to add "-literlly" option
to "cat-file"
http://article.gmane.org/gmane.comp.version-control.git/264383

Thanks to Eric, Junio and David for suggesting changes on my
first version.

Thanks to Junio for suggestions on my second version.

Changes from previous version :

* Made sure no end-user printing is taking place in
   sha1_file.c, now the printing takes place in cat-file.c
* Did not credit Junio on whose work i based my patch,
   Propoer credits given in the commit message in v3.