Added support for PouchDB

Fixes #10
Added support for grunt
Added switch to toggle continuous replication
Added replication filter to only download todo items
Added sync icon
Changed wrong filter for replication
Using Browserify for modules managing
Replaced markup parsers

Replaced Showdown with npm:Marked and textile with npm:textile.js.
Thus, this fixes #26
Split app.js in smaller chunks
Added support for recurrence

If a tickler with recurrence set is marked done, the date is
automatically updated.
Update angular to 1.2.10

Angular 1.2 now supports date input types. However, this doesn't solve
issue #27 as it is still not clear where to get angular-route.js in npm.