Added regex files, this is a small regex engine.
Merge branch 'regex'
Adding regex code into master
renaming functions, updating todo.md
updated documentation, improving API
manual.md updated
updated docs
Adding testing framework
added simple test for repl
Updated comment in test data
Added sexpr test bench
Added exit on incorrect I/O setup, but no error messages
function grep
ptr=NULL
Improved .gitignore and makefile slightly
fixed error in debug code