Improved error message with status code on unsuccessful subprocess.

listdir is not gauranteed to be sorted.

Feanil/full temp path

Importable zip files

extra_files can now include a zip file that can be also indicated in
python_path, and it will be importable by the executed code.

typo fix in Readme

Clean up CodeJail documentation

Fix temp file writing

Add instructions for changing packages

jail_code can create extra files for you from content.

The README had an incorrect app armor config.  One of the negative tests
was passing because the test program failed, but failed for the wrong
reason.  It's now tightened up to check that it is failing for the right
reason.

change log level to info so that messages will be recorded

Fix for updated logging messages

Changed logging message to yield more information

Gave things names. Gave high-level overview. Improved formatting. Gave example of how to use CodeJail

Fix some tests for faster machine

Allow programs in the sandbox to write temp files.

The test was written when I thought I could limit many small files. I've
changed it back to assert that the many files were prevented, but since
we don't prevent them yet, I've skipped the test.

This creates a tmp directory in the sandbox directory, and points
TMPDIR at it.  Allows writing files to that directory.

clarify LICENSE

make clear the viral nature does not extend to other network services

Return log warning to debug level.