#16 Multiple tiers for tabset/tabnotebook

[Erik Allaert]

these are modified versions of tabset.itk and tabnotebook.itk (diff-files attached) which implement a multiple tier feature. It is used in the tabnotebook via the new "-tiers" option:
# OPTION -tiers
#
# Specifies the maximum number of tiers for the tabs.
# If set to 0, then there will be only 1 tier, without any expansion (default).
# If set to > 0, the highest tier number will have all its tabs adjusted

# so they occupy all the space of this tier.
# If set to < 0, the highest tier number will not have its tabs adjusted - really for experimentation only

Same as "feature request" #643765.

Please note that the attached patches also deal with tickets #620806 and #514222

AND: INTENDED PRIMARILY FOR DEMO-PURPOSES, i.e. using multiple tiers is a bad idea - see http://homepage.mac.com/bradster/iarchitect/tabs.htm
(On that page, Laura Arlov is quoted from her book "GUI Design for Dummies": "One row of tabs is enough. Again: One row is enough. And once more: One row is enough.")

[Erik Allaert]

diff-files for tabset.itk and tabnotebook.itk