Add an output_loglevel argument to cmd.run*, cmd.retcode

This pull request deprecates ``quiet=True``, and adds an ``output_loglevel`` argument to these functions, allowing developers (and those running commands via the CLI) to control the loglevel at which the output from commands is logged on the minion. If the command exits with a nonzero return code, then the output will be logged at the ``error`` loglevel at minimum (higher if ``output_loglevel`` was set higher), to aid in troubleshooting. Before this pull, only ``cmd.run_all`` would log all command output if the return code was nonzero, so this also adds some consistency to the behavior.

Refs have been changed to use ``output_loglevel='quiet'`` instead of ``quiet=True``.

Package providers have had their commands (which tend to produce a lot of output) switched to ``output_loglevel='debug'``.

Additionally, a spelling error that I found has been fixed, and the ``critical`` loglevel has been added to salt.log, since this had been unintentionally omitted before.