Add dist rule

This is based on hello world example from GNU.
Use `ln` instead of `cp` in temporary dist folder
Add install/uninstall rules
Update .PHONY list
Add standard GPL header
Add required COPYING file to GPL licensing
Add AUTHORS file as per GNU standard
Add installation instructions as per GNU standards
Explain usage
Rename clean/cleanall to conform to GNU
Mention current package version
Add description of source tree
Add Copyright and license notice
Implement --version/--help support stub
Use NULL instead of 0 when appropriate
Add help/version function hooks
Futher simply the code
Implement print_help() like in GNU Hello
Implement print_version() like in GNU Hello
Define messages staticaly