Description of problem:
If one imports a calendar (local or webcal), there is no reasonable way to
figure out what dates have information in them. I initially thought the list
view would do it, but that seems to only show a month at a time, and there is no
way to adjust this to another time period (or to tell it to look at the entire
calendar).

Version-Release number of selected component (if applicable):
evolution-2.0.2-25

How reproducible:
Always

Steps to Reproduce:
1. Import a calendar
2. Look for data in it
  
Actual results:
Have to brute force, and look through month by month.

Expected results:
Be able to do a quick search to figure out when things are scheduled in that
calendar.

Additional info: