Adding support for recursive aliases.

Alias expansion is now a loop. If you define

alias A=B:A
alias B=C:B

then A will expand to C:B:A.

Also added a short section to the manual about this.
fixing problem with previous commit if no aliases are registered
Adding tests for recursive aliases
Adding option --recursive-aliases, adding documentation to man-page and manual
Fixing two GCC warnings
Merge pull request #247 from ecraven/master

Adding support for recursive aliases.
Merge pull request #248 from ecraven/fix-warnings

Fixing two GCC warnings
Adding option --no-aliases to completely disable alias expansion
Merge pull request #249 from ecraven/opt-no-aliases

Adding option --no-aliases to completely disable alias expansion
Adding documentation of options to man-page from manual. Fixing a few minor typos and mistakes.
Merge pull request #250 from ecraven/update-manpage

Adding documentation of options to man-page from manual.