Support for "text/x-vcard; charset=utf-8" as a value for getcontenttype
Updated the configuration handling.

The Configuration Parser now relies on a collection of Section
Parsers. The Configuration Parser reads the file sections one at a
time, using the matching section parser. The produced data sets are a
wrapped in a Namespace, and can be unique or belong to a collection.
The Configuration Parser returns all those data sets in a top-level
Namespace. The data read on the command line is also stored in this
top-level Namespace. Its content depends on the tool used.

pycardsyncer is broken at the moment, since it is not aware of the new
WebDAV accounts configuration.
More configuration handling updates.

Configuration checking is now split into check, check_accounts and
check_property. All the default parameters are checked in the root
Configuration object.

More exceptions are catched during parsing. Useless check of
sqlite.path is removed (since a default value is provided if missing).
Modified the syncer for the updated configuration.

For now, it only considers the first defined account.
Added a parameter to bypass the accounts checking.

This is specially useful for tools working only on the database (like
pc_query) which thus never ask for a webdav password.
Cosmetic change on configuration dump.
Added the --account option on pycardsyncer.
syncing multiple accounts should work now

pc_query and pycard-import are still broken
Merge branch 'multi_account' of github.com:geier/pycarddav into multi_account

Conflicts:
	bin/pycardsyncer
	pycarddav/controllers.py