Initial code stub for generating the preference panel
for session import options.
Initial implementation stub of import session
More implementation for import session.
Remove all import storage configuration now when they are avail
in preference panel.
Make use of a import session instance in camera jobs.
Move logics for evaluating a new filename if exists into import session
from the camera import job.
Initial clean up  of capture view and added use of import session.
Merge remote-tracking branch 'upstream/master' into session
Refactor tethering to use new session import per capture job
to detach it from the view itself.

- Rewrote camera jobs to use a session import.
- Make use of the new camera job in camera.c
- Removed duplicated code and clean up of the tethering view
Fix shared camera settings.
Check if we got a pattern in import session.
Wait for all captures to be downloaded before exiting capture job.
Use a mutex/cond for capture job to prevent job finish
before all camctl image download events have been processed.
Merge pull request #424 from hean01/session

Import session