[kde-guidelines] Styleguide: Spin box

[Heiko Tietze]

I adopted the substructure, duplicated some advices about erroneous input from 
line edit to the behavior section and added the recommendation to always use 
suffixes.

http://techbase.kde.org/Projects/Usability/HIG/Spin_Box

I'll add categories to the pages. 
[[Category:Usability]]
[[Category:Behaviour]] //1st level in hig structure
[[Category:Editing_and_Manipulation]] //2nd level in hig structure
[[Category:Constrained_input]] //3rd level in hig structure

Depending on how we want to use the categories we should consider to do 
something like [[Category:Behaviour|Spin Box]] which sorts the page into S 
rather than P. As example I created http://techbase.kde.org/Category:Behaviour