Optional lazy connect to SFDC by setting SF_LAZY_CONNECT. Fixes #71

It allows start of application even if SFDC is not currently accessible.
Fixed tests for lazy connect
Implemented recovery after repairing broken SFDC. #71
Security for tests: never send private data to nonexisting hosts
Locking for SF_LAZY_CONNECT.
default person account to false when not specified, fixes AttributeError
Merge pull request #72 from hynekcer/lazy-connect

Lazy connect, fixes #71
Merge pull request #73 from cloudanswers/default-person-account-check

default person account to false when not specified, fixes AttributeError
Fixed for easy adding new tests to Tox and Travis. Fixes #74
Merge pull request #77 from hynekcer/test-tox-travis

Fixed for easy adding new tests to Tox and Travis. Fixes #74
Fixed tests for incomplete test project directories after switching git branches
Fixed some comments and messages
Fixed the demo homepage to work also with a normal Account.

It should also never raise exception for any user input.
Fixed __repr__ for query to be more exact, though less intuitive.
Removed RoutedModelAdmin as not important, replaced by an empty stub.

RoutedModelAdmin only explicitely discovered the database name by calling
database routers configured in "settings.DATABASE_ROUTERS". That is the same
what is otherwise arranged implicitely a few later by Django.
Removed RoutedModelAdmin also from the demo application.
Moved "reauthenticate" from backend.query to auth module.
Configured coverage with a more clear filename.
Implemented defer(..) and only(..) queryset methods

Output fields can be specified by also in some internal methods.
Enabled and improved tests for deferred fields queries.