check_ocsp made more dynamic

* Better suited for general purpose use now
* prints help dialog on invalid usage
* All variables like certificate file and issuer can now be set from the command line
chech_ocsp_hard.sh renamed to check_ocsp_hard.sh

I believe "chech" is a typo
Merge pull request #4 from palli/dynamic_ocspcheck

Make check_ocsp_hard.sh more suitable for general purpose use