wip/flickr branch: Initial commit

New flickr miner files.
Makefiles and d-bus files modified
data: add a DBus service file for org.gnome.Documents.FlickrMiner

https://bugzilla.gnome.org/show_bug.cgi?id=700897
Work started, backup commit
Flickr-miner: Synchronous version with pooling

Since GdMiner object frees job after end of query_* function, the query
needs to do everything synchrounously. There were a problem with doing
it all synchrounously because of asynchronous adding of sources. This is
not still solved. This version uses GThreadPool for browsing containers.
It hangs when it comes to browsing not-root containers, which it did not
do when it was asynchronous or when the functions were used standalone.
Flickr miner: asynchronous version, working but..

Crashing for SIGSEGV after work is done. Im probably freeing
some memory twice.
Flickr miner: SIGSEGV and assertions solved
wip/flickr: Start query only when refresh_db signal is recived

Also some comments were added
wip/flickr: Some aestetical changes
wip/flickr: tracker capabilities uncommented

NOTE: not debugged yet, but seems working
in gd-miner-tracker.c I deleted some debugging messages I added earlier.
wip/flickr: process account separately

Earlier I was forced to browse all sources from accounts at once, but
now, when comes the new naming of flickr grilo sources, I can find only the one
source which I need and browse only this one. GdMiner then calls
create_service on each present account in GOA.
wip/flickr: process entry

Added all functionality to process entry
wip/flickr: nie:mimeType added
Merge branch 'wip/flickr' of git://git.gnome.org/gnome-documents