Iplement makefile magic

Use the $< and $(addprefix ...) makefile macros.
Fix undefined malloc error

Include <stdlib.h> instead of <malloc.h>.
I am assuming that <malloc.h> was a typo. This fixes the build.
Ignore flex and bison generated files

Remove flex and bison generated file and add them to the .gitignore.
Improve make clean to remove all generated files

Add mt_parser.* and mt_lexer.* to make clean.
Merge pull request #3 from cknadler/master

Improve makefile and fix build