Supermann

- Upgraded to most recent version of `psutil` (`2.1.1`)
- Replaced or changed various metrics
- Replaced `argparse` with `click` and made improvements to CLI
- Replaced `file` argument syntax with `supermann-from-file`
- Removed `--memmon` option and memory monitoring plugin
- Added documentation on `Read the Docs <http://supermann.readthedocs.org/en/latest/>`_
- Many other minor fixes and improvements

- Set command line defaults correctly
- Added `process:%:uptime` metric
- Improved exception handling
- Log basic information about Riemann on startup

Adds support for `path`-style argument files.

Replaced argparse 1.2.1 with 1.1, as versions of argparse above 1.1 are not hosted on PyPi and so will not be installed by pip when using the default settings.

This replaces the internal Riemann client (`supermann.riemann`) with the riemann-client package ([python-riemann-client](https://github.com/borntyping/python-riemann-client)).