Removes banner and stig-fix rpm.

* Adds .gitignore to ignore iso which is created in the same
  directory.

* Code indicates it is licensed GPLv2 however the LICENSE file
  contained the Apache Licence.

* Added arguments to createiso.sh to take paths to needs files
  - banner
  - stig-fix rpm
  - rhel server ISO

* Converted tabs to spaces.

* Corrected typos.