Master 3.0 merge

Not intending this to be accepted. Rather I'd like this to be discussed as a step closer to the merging of these branches.

*Example Deployment:* http://115.146.94.32/

## Changes

### Features
Dataset page has contextual link back to parent experiment (and shows other related experiments)
New diffraction image filter (now does preview images using CCP4 'diffimage' binary)
Images stored in datafile parameters now show in preview images (including slideshow)
Asynchronous email functionality
Import Staging Files now works as an asynchronous task with email notification
Import Staging Files now has ajax loading of directory nodes in interface for performance
Overhauled sharing interface. Sharing settings live in a tab in the experiment view
Group management and creation interface overhaul
User creation function (for users to create other users in the system)
Numerous UI tweaks
Experiment description now supports HTML
Filepicker.io option added as an alternative (HTML5 based) upload form
Can automatically generate docs now via command-line
Contextual Views: plugin architecture for optional custom dataset and datafile views based on presence of certain schemas

### Bugs that were fixed
dataset / data file filter doesn't respond to return key press
editing an experiment with 1 user failed, saying it doesn't exist
users without a userprofile object crashed
level of access (eg. public) level not updated in experiment interface when changed
no confirmation/error feedback message for creating groups
group management doesn't check permissions on interface level
dataset tiles in experiment page don't display correctly on mobile
metadata modal box doesn't close on close button
pagination doesn't display correctly
mets export produces datafile metadata sections for files that have none
mets import doesn't import files with no datafile metadata
verify files task tries to verify files in the process of staging and fails, growing the queue infinitely
locked celeryd tasks taking resources (now has fairly liberal default time cutoffs for independent workers e.g. several hours)