* refactors CheckableMixin and RecordableMixin into CheckableObject and RecordableObject
* adds ShareableObject for wrapping share related fields and functionality
* adds share functionality to EcoAccount and EMA, just like Intervention
* adds NewEmaForm and EditEmaForm
* refactors ResponsibilityData related form fields into reusable mixin CompensationResponsibleFormMixin
* used in NewEcoAccountForm and NewEmaForm for easier maintaining and reducing amount of code
* refactors templates /xy/new/view.html into /xy/form/view.html since the same template file is used for new and edit forms
* refactors documents and file upload to be distributed into different subfolders, depending on the type of document (InterventionDocument, RevocationDocument, ...)
* refactors Document model into AbstractDocument
* subclasses RevocationDocument, InterventionDocument, COmpensationDocument, EmaDocument and EcoAccountDocument from AbstractDocument to provide proper functionality for each
* adds new specialized routes for each new document type (opening, removing)
* drops generic get and remove routes for documents
* fixes created timestamp in detail views where modified needs to be displayed
* adds fallback timestamp if data has not been edited, yet --> show created timestamp
* fixes bug where deleting of certain data didn't redirect to the index view
* adds quality_check() method for EMA, needed for recording
* adds all functions which are provided for compensations to EMA
* adds/updates translations
* adds Ema model (basically Compensation inherited)
* adds index view for EMAs
* fixes drop-down link bug for menu 'More' in navbar
* refactors some more forms to use process_request()
* adds modified attribute to BaseResource for easy last_modified check
* adds setting of modified attribute in all places where UserAction.EDITED is added to log
* adds EMA_ACCOUNT_IDENTIFIER_LENGTH and EMA_ACCOUNT_IDENTIFIER_TEMPLATE to ema/settings.py
* adds EmaAdmin to ema/admin.py
* fixes wrong title in intervention detail view html for revocations
* adds support for subtitle variable to BaseTable and generic_index.html
* drops next_version attribute from models
* adds/updates translations
* adds default ordering for UserActionLogEntry
* removes extra ordering in log modal rendering
