Feature #3622: added commitee presence percentage this year

Fixed name of the computed field "meetings_count" to
"meetings_percentage" (to reflect its function).

Added the computed field "meetings_percentage_year" and added an index
on the CommitteeMeeting's date field for it (migration added).

Added a <p> tag to display the date in the committee_member_photos
template - needs translation.
Feature #3622 addition: fixed the yearly percentage calculation
Feature 3622

Merge branch 'master' of https://github.com/yoniYalovitsky/Open-Knesset
Update translations