Adding identificator to show it in the interface, developing branch.
Added 2 parameters to limit the download size, and how many articles are downloaded by request to the server.

Alerts to detect size download anytime you connect to the server.

This patch catch any exception in case data is not able to be stored in localStorage
Merge pull request #33 from Alvarord/master20140429-issue30

Limiting the size of the download so localStorage doesn't get full, thanks @Alvarord