some fixes in format()
Merge pull request #6 from groessler/something_to_pull

some fixes in format()
added KNOWN_ISSUES file. fix bug when trying to read null variables in history.c.
some cleaning
Delete .string.c.swp
Update Makefile

Add install rule, remove all the custom per-file rules.
Makefile bugfix: Respect PREFIX in 'make install'
Merge pull request #9 from trozamon/make

Makefile fixes - Many thanks trozamon!!
fix in file permissions