Changes in setActorByName, refs #7327

- Stop saving IO inside the function
- Chech populated events and relations first
- Check relation and events for other IOs in the same repository after
Code clean-up, refs #7327
Make finding aid job use "Site Base Url" #7693
Fix DC template HTML escaping issues. refs #7658
Added features to OAI-PMH API. refs #7469

Added embedding of digital objects in records returned
by OAI-PMH queries. Added API key authentication.

Digital objects are embedded in the <about> tag at an
Atom XML feed.

API keys can be generated for individual users, via the
user admin interface, and optionally required for authentication.

Smaller changes:
* Removed OAI disabled page.
* Got rid of redundant OAI-related setting.
Enable escaping_strategy
Expect sfOutputEscaper in QubitRoute
Expect sfOutputEscaper in QubitAcl::check
Checking properties of in escaped ES docs
Use $sf_data->getRaw(...) when needed

There are places where the way the code is written just don't work with escaped
objects. For example, getAll() in a parameter holder does not return an array
anymore but an object that implements ArrayAccess. We use the + operator to
append that to another array in multiple templates, but that won't work
anymore.

It seems that using the raw version of the parameter holder is secure in the
cases used in this commit, e.g. for links generation the HTML entities are
still escaped somewhere else.
Use raw validation messages when needed

In certain pages we use the validation framework to validate the contents
without really showing them, so no need to escape them. In addition, the
validation messages where customized with HTML links to metadata standard
documentation, these HTML entities can't be escaped or they'll break.
Fix render_treeview_node, use raw object
Escape str from obj created within template
Escape entities in popular component
Avoid type hinting for escaped objects
Raw access to getVarHolder when needed
Fix escaping in singleFacet
Stop type hinting in get_search_i18n_highlight
More escaping fixes