cLock: Make the list of calendar entries scrollable (max. 10 entries)

This changes the rendering and calendar data aquiration quite drastically, as
a new widget service had to be introduced.

Change-Id: I5bcdaa952acde2caa5a3f04b2c8c98868fd7cbfb
Merge branch 'cm-10.1' of github.com:CyanogenMod/android_packages_apps_LockClock into cm-10.1