Release Mayor 6.0.0 release

Release 5.2.10

Release 5.2.9

Release 5.99.90 "6.0 Beta"

Release 5.2.8

Release 5.2.7

 - Fixed compilation on MacOS

 - All Vala bindings and Vala extensions are built by default using --enable-vala,
   added --disable* switch to disable some or all of them
 - Fixes on outdated unit tests
 - Removed unused Vala extensions
 - Translations:
	- es (Daniel Mustieles)

Long time to release this new version, but here is it.

This is a bug release, including many fixes and multi-threading stability.

Embedded SQLite has been updated to 3.8.11.1 while SQLCipher has been embedded for release 3.4.2.

Release 5.90.1 a maintenance version of 5.90.0

Tagged 5.2.4