build: Make sure to build examples, doc and po last
build: Make sure to build examples, doc and po last

It seems more natural to compile examples after optional libraries as
you could have an example illustrating one of those libraries.

Build the docs and po files at the end too, trying to group the
compilation of C files together.

djdeath/cogl,djdeath/cogl-android,djdeath/cogl,djdeath/cogl,gcampax/cogl,gcampax/cogl,collects/cogl,gcampax/cogl,Distrotech/cogl,gcampax/cogl,djdeath/cogl-android,Distrotech/cogl,djdeath/cogl-android,spatulasnout/cogl,collects/cogl,Distrotech/cogl,Distrotech/cogl,spatulasnout/cogl