Consistent help

[peter.zrnko]

I think it will be of much help and not so much work to add some pages to help file regarding:
- showing and hiding things at different levels (project, diagram, element)
- formating things at different levels (project, element, elemnt in diagram) - colours, fonts etc.

And link these pages form every help page touching these topics.

(Another option is to rewrite the GUI and make make it trasparent for users - Something like do you want to set xxx ? And do you want to set it on project level diagram level or element level?)