Simplifying apache config

Removing 'wsgi' and 'main', using a number for the timestamp (same as
in mf-geoadmin3), caching the loader.js and moving the generated doc
to its own directory to avoid side effects with services.
Updating examples to consistently use the local loader.js
Merge pull request #877 from geoadmin/mom_api_loader_cache

Rewriting clean versioned API url