Add contributing document
Prevent pre-populating date fields

On the tree detail page, the actions edit->save->edit would cause any
date fields on the page to be populated with the current date. This was
caused by the fact that calling "getDate" on the date picker will always
return a value, even if the text box to which the date picker is
connected is empty.

Fixes #1581
Merge pull request #1586 from jwalgran/topic/prevent-prepopulating-date-fields

Prevent pre-populating date fields
Show "Boundaries" checkbox in Leaflet layer control

This lets users toggle boundaries (e.g. neighborhoods, zip codes) via a checkbox in the Leaflet layers control.
Comment Moderation prototypes

Comment Moderation Page

Needs reviewed by Deb
Merge pull request #1589 from RickMohr/comment-moderation

Comment Moderation prototypes
Merge pull request #1587 from RickMohr/boundaries-checkbox

Show "Boundaries" checkbox in Leaflet layer control
Update scenarios templates CSS.
Merge pull request #1591 from kdeloach/topic/update-scenarios-template

Update scenarios templates CSS.
Integrate comment moderation prototypes

Misc:
* Flag-related stuff is not yet implemented
* rename `comments_review` function as `comment_moderation` to match language used elsewhere
* utility function `detail_link` now supports linking to users and to `MapFeature` subclasses like `Plot`
* Fix initialization of photo review page
Merge pull request #1593 from RickMohr/integrate-comment-moderation

Integrate comment moderation prototypes
Lint removal
Unlocalize comment id in HTML attribute

Saving threaded comments was failing because id 1000 was being added to
the DOM as "1,000"

Closes #1594
Add model and migration rules for TreeFavorite
Merge pull request #1595 from steventlamb/topic/add_tree_favoriting

Add model and migration rules for TreeFavorite
Merge pull request #1597 from jwalgran/fix/threadded-comment-unlocalize-id

Unlocalize comment id in HTML attribute
Add leaflet-draw 0.2.2 plugin.

This is for drawing the polygon feature for modeling tree distributions.
Merge pull request #1600 from kdeloach/topic/leaflet-draw

Add leaflet-draw 0.2.2 plugin.
Fontello icon substitution

Fontello icon substitution
Add comment moderation action endpoints

This includes the flag/unflag endpoints for use by the plot detail page
as well as the moderation endpoints for hiding, archiving, and flag
clearing.

I chose to create an EnhancedThreadedCommentFlag model because the
built-in CommentFlag does not support hiding, and I though having our
doubly-inherited comment model link back to another inherited model
would be too confusing, or perhaps impossible.