added version field to class

current implementations of the MetadataSource are still compatible, the
version field simply remains null unless argument is passed to new
constructor
tool items now clickable; fix cellstylegenerator

items in the tool column are clickable, showing a notification of the
tool version (obtained from updated MetadataSource class)

corrected cellstylegenerator section so rows should now color properly
Merge branch 'master' into test-documentation