Highlight current calendar in the list

Ticket #113; resolved via JS
Forbid '#' in meeting location

Ticket #118; right now char '#' is forbidden in the 'Location' field. Also
added filter to autocmplete function so no strings containing '#' shows in the
autosuggest pool
Highlight selected calendar

Fix for Ticket #113 - this time jinja-based solution
Had to rename some variables as the loop {% for calendar in calendars %} was
using calendar variable that was already declared in the global scope so I
couldn't make calendar.calendar_name == calendar.calendar_name comparison

Also added `margin-left: -2px;` so that the rectangle looks a little better on
the left side.