Shell doc: Remove shell script. Rewrite PHP script.

Split classes to several files.
Separate parsing and rendering code.
Warning: HTML renderer is not functional yet.
Merge branch 'new_sh_doc' into develop
Add phool lib for option parsing. Various fixes
Rename shell_doc_md.php to shell_doc.php (because it does not generate md only)
Merge branch 'new_sh_doc' into develop
Merge branch 'release-1.2'