fix(upload): generate non-external urls to make it work with proxy
fix(blueprint): set blueprint url prefix to match eve
fix(url): define server name to return full urls

It's using `SUPERDESK_URL` environment variable which is parsed
and used for `URL_PROTOCOL`, `SERVER_NAME` and `URL_PREFIX`.
Revert "fix(upload): generate non-external urls to make it work with proxy"

This reverts commit 5f8f133a6f4dcc38e0e914458894d3bb363d2157.
fix(settings): remove default URL_PREFIX

there is no prefix by default, only when set
added 4 more fields to the items schema
deleted one  field from the items schema

close #55
fix(setup): add setup.py with initial config
fix(archive): remove archived property from archive api

SD-330
feat(renditions): update system rendition sizes

SD-326
SD-315 : _created and _updated fields display invalid date
SD-324 : Upload images to the Content Archive