DOC : added google tarcking code
Merge pull request #3686 from tacaswell/tracking

DOC : added google tarcking code
Merge branch 'v1.4.1-doc' into v1.4.2-doc
Merge pull request #3743 from Carreau/nopylab

DOC : remove mention to %pylab
Merge branch 'v1.4.2-doc' into v1.4.x

Merge doc branch back into the maint branch