Added ENABLE_MKTG_SITE to Features
Added myself to author file
Switch from Rake to Paver
Change `if not args.skip_collect` to `if args.collect`

Simpler and clearer
from __future__ import print_function

and print errors and warnings to sys.stderr
write_stderr() function is unnecessary
Pull Paver requirements out into a separate file
Insert *right* at the front
Changed str->unicode in common/djangoapps/utils/.

LMS-2436
Display error page templates, for testing purposes

This commit allows us to test the server error template by visiting `/500`. This
way, we can catch errors in our error templates, instead of having infinitely
recursing errors.
Fix Studio's XBlock dependency loading issues

STUD-1465

Changed the XBlock rendering logic to use promises to track asynchronous tasks.
Each dependency is then only loaded once the previous one has completed, and the
XBlock initialization only happens once all dependencies are loaded. This gives
XBlocks the same semantics in Studio as they get when shown directly on a page.
Added template for iFrames. [BLD-611]
Submission history view not internationalized.
LMS-2167
BLD-951: Fix flaky tests.
Removing ipython from edx dependencies.

Ipython is not strictly required to run edx-platform. It can
be setup as part of Vagrant provision scripts, or manually
by each developer as required in specific cases.
Some more str->unicode fixes in instructor and courseware apps.

LMS-2429
i18n: make emails in lms translatable

The email texts in lms/templates/emails are not extracted by rake i18n:generate because the babel_mako.cfg does not include them.
And a several emails are not translatable because they do not use ugettext.
Documentation for static page changes

STUD-1347
Help paver find the theme directory
fix paver theming on devstack (SERVICE_VARIANT support)

When running in devstack, you need to set the SERVICE_VARIANT so that
assets.py knows what environment file to use.  Recall that in devstack
we have all our settings in ../lms.env.json, not just ../env.json.  So
you need to run like this:

    SERVICE_VARIANT=lms paver lms --settings=devstack

Previously you'd get this error:

    Warning: could not find environment JSON file at 'lms.env.json'

Note there is no path on the file, that's the bug.  By making
self.REPO_ROOT absolute, we can walk up the tree and correctly find
the file, which is /edx/app/edxapp/lms.env.json fwiw.