Alphabetise task lists

Hi,

Nice app; simple, tidy, and although I'm not a freelancer but am just using it to track my daily time generally I've found it to do the job nicely.

Would you like to have the task list sorted so some users can find a task a little easier than when they added it?

I've added a preference and used it when fetching all tasks from the db, both in the main view and the time edit selector. The only gotcha is that it needs the list / app to be closed and re-opened, but I don't think users would change it all that often for it to become a nuisance.

Below is a few screenshots of:
* the bilable>title sorted list and in the time edit screen
* the preference enabled & disabled
* the billable>id sorted list (i.e. original functionality)

![1-list-unsorted](https://f.cloud.github.com/assets/193455/594789/8f003014-cab4-11e2-9860-91403dbae4b3.png) ![2-edit-sorted](https://f.cloud.github.com/assets/193455/594790/8f0a707e-cab4-11e2-9a3a-1a68395b8b03.png)
![3-pref-on](https://f.cloud.github.com/assets/193455/594787/8ee96636-cab4-11e2-95c4-f9168a97b695.png) ![4-pref-off](https://f.cloud.github.com/assets/193455/594788/8efdc734-cab4-11e2-880d-98f1a5033bd3.png)
![5-list-sorted](https://f.cloud.github.com/assets/193455/594786/8ed0246e-cab4-11e2-988d-57a1431a4f2a.png) 


Cheers.