Added chmod check to execute.copy tests.
Added filecopy test for chown

Tests the file chown after a ugo.is_root test passes.
Separated file modification actions.

There are now a set of modify actions, specifically chmod and chown,
which are components of the AL generated by a file block where action
is 'copy'. This should extend to other contexts as well in the future.
Includes the necessary updates to tests to make this work.
Refactored file create and chown handling.

Now does dispatch on action type and inserts actions into it if it is
an AL. To make this clean, includes append/prepend support for ALs.
Tests fail at present.
Improved file action behavior when underspecced.

Underspecified file actions now do not always fail. Instead, the action
construction code first creates a base action with minimal requirements,
then adds any actions that it has sufficient specification to perform,
or has a need to perform. This creates uniformity between handling of
chown, chmod, backups, and any other desired auxiliary actions.
Test cleanup to handle new File action structure.

Tests now correctly examine the results of converting file blocks to
actions. Required heavy modification of the tests that ensure that
action generation fails with missing attributes, as they were no longer
correct with the new behavior.
Added some testing for DirCopyActions.

Just tests the string conversion and that execution invokes
shutil.copytree
Added some basic execute.modify tests.