Allow for relative paths by using abspath

relative pathing comes in handy on occasion, particularly when
delegating to localhost and running some command out of your playbook
repo. Making use of os.path.abspath will allow for the full path to
chdir and executable to be discovered if not provided.

library/commands/command

@@ -33,8 +33,7 @@ description:
      - The M(command) module takes the command name followed by a list of space-delimited arguments.
      - The given command will be executed on all selected nodes. It will not be
        processed through the shell, so variables like C($HOME) and operations
-       like C("<"), C(">"), C("|"), and C("&") will not work. As such, all
-       paths to commands must be fully qualified
+       like C("<"), C(">"), C("|"), and C("&") will not work.
 options:
   free_form:
     description:
@@ -192,17 +191,15 @@ class CommandModule(AnsibleModule):
                 params['removes'] = v
             elif m.group(2) == "chdir":
                 v = os.path.expanduser(v)
+                v = os.path.abspath(v)
                 if not (os.path.exists(v) and os.path.isdir(v)):
                     self.fail_json(rc=258, msg="cannot change to directory '%s': path does not exist" % v)
-                elif v[0] != os.sep:
-                    self.fail_json(rc=259, msg="the path for 'chdir' argument must be fully qualified")
                 params['chdir'] = v
             elif m.group(2) == "executable":
                 v = os.path.expanduser(v)
+                v = os.path.abspath(v)
                 if not (os.path.exists(v)):
                     self.fail_json(rc=258, msg="cannot use executable '%s': file does not exist" % v)
-                elif v[0] != '/':
-                    self.fail_json(rc=259, msg="the path for 'executable' argument must be fully qualified")
                 params['executable'] = v
         args = r.sub("", args)
         params['args'] = args