added support for reading a list of repos (-i <file> or --include <file> flag) to perform operations on instead of using teh repos in current directory
updated help text and readme file with -i flag documentation
updated help text with -i flag
Merge branch 'repos_from_file' of git://github.com/ostengaard/gitall into ostengaard-repos_from_file

Conflicts:
	gitall

Changed switch for including file from suggested "-i, --include" to "-I, --include-from"  to reserve --include switch for future command line specification, and to mimic style from e.g. rsync.