ekeyword: Add file_parse, get_portdir and get_architectures functions.

ekeyword: Add file_parse, get_portdir and get_architectures functions.
	file_parse is a file parser which strips trailing and starting
	whitespace, replaces multiple whitespace by one whitespace and ignores
	comments. It returns an array.
	get_portdir uses portageq to determine the PORTDIR value.
	get_architectures reads $PORTDIR/profiles/arch.list and adds all
	available architectures to the %ARCH hash which can be used for
	validation.

svn path=/trunk/gentoolkit-dev/; revision=787