Full restructure (and new 'delete' action) of the 'local' deployment module

This is a full restructure of the 'local' deployment module with the following changes:

- 'delete' action added:
 - New 'remove_file' parameter added.
 - 'recursive_delete' helper function added.

- 'command' function modified:
 - All actions moved to a new switch/case structure.
 - 'check_source_exists' helper function added. It checks the existense of the source_file parameter and the existence of the file pointed by this parameter.
 - 'check_target_exists' helper function added. It checks the existence of the target_file parameter and create the required directory.