Merge pull request #11 from ByteInternet/set-rc-when-execvp-fails

Set RC when execvp fails
Credit contributor of previous commit
Add manpage
Restructure README so that a manpage can be generated
Remove superfluous manpage: it is now generated
Merge branch 'add-makefile' into create-manpage
Add manpages to Makefile and README
Merge new manpage system