Add a bug "blocked" state

[edmorley]

From the newsgroups:

Tim Taubert:

I we would like to suggest that we add another state "blocked" so that I
could clearly mark a bug as blocked/stalled instead of only saying so in
the "Coordination" field.

[edmorley]

mozilla-weekly-updates/weeklyupdates/templates/common.xhtml

Line 181 in e2e9c5c

<div class="dropdown">

mozilla-weekly-updates/weeklyupdates/model.py

Line 180 in 700238b

bugstatuses = {

mozilla-weekly-updates/weeklyupdates/static/css/ui.css

Line 186 in 1f14ee9

.glyphicon.status-notstarted {

[edmorley]

Closing this out to de-clutter my GitHub open issues dashboard since I believe this tool is deprecated.