argparse & logging (#92)

* introduce logcommand.Lager, Whipper(); use argparse for whipper image commands, stub logging

* update Lager docstring to mention config.Config()

* make incorrect subcommand and --version work on toplevel command

* migrate accurip show, expand Lager, do not attempt to return from Lager.__init__.

* migrate offset find, add Lager.error

* correct offset find drive symlink handling

* migrate drive

* change Lager.__init__(prog) to arg from kwarg

* but actually

* remove Whipper.usage

* add and use Lager.device_option() context manager

* help I married an axe murderer

* use unified options namespace for entire command tree

* migrate whipper cd without comprehensive config loading

* switch to logging module

- use logging instead of flog for non-extern modules
- use WHIPPER_DEBUG and WHIPPER_LOGFILE env variables

* convert self.log calls to logger.debug

* convert self.error calls to logger.error

* remove log.Loggable, use logger not logging

* Logging conversion continues

- Convert log.* calls to logger.*
- Remove morituri.common.log imports

* remove morituri.common.log from tests

* remove extern/flog, bare minimum Debug conversion

* update README for logging changes

* update soxi to use logging

* refactor Lager for more declarative subcommands

* Refactor Lager.device_option:

- inline into __init__
- throw IOError instead of Exception for missing drives
- remove CommandError checking in rip/main

* rename rip to whipper in rip.main

* convert rip.debug commands

* Rename logcommand.Lager to command.BaseCommand

- remove command.CommandError occurrences
- remove python-command external module

* remove submodules from README, update rclog formatter

* update minor ambiguity in readme for command invocation

* update version number to match setup.py

* remove gitmodules

* update version number in tests as well (boo)

* convert logger.error to logger.critical

* Change morituri.rip to morituri.command

- mv common.command to command.basecommand
- move TEMPLATES used only by rip.cd out of rip.common
- update entry point for command to command.main

* update basecommand documentation

* go pyflaking: import fixing

* replace self.stdout with sys.stdout

* remove BaseCommand.config, alphabetise imports

* convert self.stdXXX leftovers

* convert last getRootCommand to config.Config

* convert last getExceptionMessage's to str

* change musicbrainz useragent to whipper

morituri/program/arc.py

@@ -1,6 +1,8 @@
-import logging
-from subprocess import Popen, PIPE
 from os.path import exists
+from subprocess import Popen, PIPE
+
+import logging
+logger = logging.getLogger(__name__)
 
 ARB = 'accuraterip-checksum'
 FLAC = 'flac'
@@ -33,18 +35,18 @@ def accuraterip_checksum(f, track, tracks, wave=False, v2=False):
     arc_rc = arc.returncode
 
     if not wave and flac_rc != 0:
-        logging.warning('ARC calculation failed: flac return code is non zero')
+        logger.warning('ARC calculation failed: flac return code is non zero')
         return None
 
     if arc_rc != 0:
-        logging.warning('ARC calculation failed: arc return code is non zero')
+        logger.warning('ARC calculation failed: arc return code is non zero')
         return None
 
     out = out.strip()
     try:
         outh = int('0x%s' % out, base=16)
     except ValueError:
-        logging.warning('ARC output is not usable')
+        logger.warning('ARC output is not usable')
         return None
 
     return outh