Make session data delete possible with active_record_store

Conflicts:
	db/schema.rb
Correct `#user .logged-in` ids and icons

* The env admin link and the user pannel had the same controlpanel id.
* The user icon is now recovered.
* The #manage-enterprises icons was croped.

Closes ActionItem2817
finishing action item 2722
Finishing unit test action item 2722
Fixes the layout of nested comments on the wall

  - Makes the hierachy clearer with padding.
  - Removes a white border that was giving the impression of broken
  layout.

(ActionItem2726)
(ActionItem2725)
Adds user icon for null avatar on user menu

That commit makes gravatar helper to work on this context.
stoa_plugin: improve webservice

   * Creates a smart api to define categories of fields.
   * Inclusion of sensitive and heavy fields categorization
   * Possibility for creation of custom fields

(ActionItem2832)
change_password: accept email or login

Also including support for other fields later.

(ActionItem2857)
forgot_password: allow password recovery with email OR login

Also provides infra to any other field in the future.

(ActionItem2857)
stoa: recover password through usp_id too

Also provides hotspot for plugins to add new fields for password
recovery

(ActionItem2827)
stoa_plugin: remove sensitive fields from person api

(ActionItem2832)
stoa_plugin: add tags to person api

Also include person_api test file that was not added on previous
commits...

(ActionItem2832)
Merge remote-tracking branch 'origin/master' into stoa-webservice
Adds filter by role in memberships listing
New style for box-organizer on 'edition mode'
Fix bug show controllers option block .feed-reader-block

Sign-off-by: Valessio Brito <valessio@gmail.com>
Sign-off-by: Leandro Alves <leandrosustenido@gmail.com>
Add fix hidden buttons in all .block

(ActionItem2810)
Create a new template "Left bar and Footer"

Signed-off-by: Leandro Alves <leandrosustenido@gmail.com>
Signed-off-by: Valessio Brito <contato@valessiobrito.com.br>
change-password: changing labels

Field -> What do you remember?
Value -> <no-label>
custom_forms: return to profile main page when cancelling submission

AI2870