Admin menu validation fix and basic cleanup in bbPress admin functions file

[Simek]

There is a validation problem because of DIV insertion inside link. Solution how to fix it is simple - just replace DIV with INS tag.

I've also made a basic cleanup in "functions.bb-admin.php" file.

Everything was tested on my test instance of bbPress.

If you like those changes I can prepare more fixes like this and some small code enchantments in future.

[sambauers]

I think SPAN should be used instead of INS if this is considered a problem. A SPAN will probably need to have display:block added to it's style as well.

[Simek]

We can use here also like you suggested SPAN with "display:block" but this produce new validation warning because SPAN tag shouldn't be empty.

[johnjamesjacoby]

Closing as wontfix. The stand-alone version uses the same method as WordPress does, and the bbPress plugin for WordPress will inherit a similar issue.