Drop modules from discontinued services or urls

[chirale]

I know that this is cross-repository issue, but it may affects a normal installation since usually broke the functionality and add some urls that can be hijacked. Here and in contrib (c) there are some discontinued services:

• (c) Digibug
• (c) Picasa Faces
• (c) export_facebook (defunct application)

And other external URI are gone:

• (c) polar rose (cdn domain is gone)

This is an incomplete list, please note that this list can be different to obsolete modules, even if those may be treated the same way.

A cleanup can be applied in different ways:

• blacklisting modules using an enabled-on-installation core module or setting on gallery3
• removing from core or contrib from the forked repo

This issue may remain open to list other elements with broken urls or services.

[bwdutton]

Sure, I removed these modules from the contrib repo. https://github.com/bwdutton/gallery3-contrib/commit/361742ca288eeaad2dd60272de9e9eadfbff8eca