BookElement rendering (in progress)
Merge branch 'master' into tags-master
better intro style
Merge branch 'master' into tags-master
synchronisation with intro branch
Merge branch 'master' into tags-master
synchronisation with intro branch
Merge branch 'master' into tags-master
sync with intro branch
Merge branch 'master' into tags-master
book popup layouts
Merge branch 'master' into tags-master
catalog => catalogue
Merge branch 'master' into tags-master
color => colour
Merge branch 'master' into tags-master
English intro
Merge branch 'master' into tags-master