Hide Ask navigation link if Ask is not enabled.

* Added check for {block:AskEnabled} around Ask menu link.
* Added missing closing li tag.
Added support for tags.

* Added tag output if {block:HasTags} returns TRUE.
* Added default styling for tags in multiple display widths.
Merge pull request #1 from markdorison/ask-menu-link

Hide Ask navigation link if Ask is not enabled.
Merge pull request #2 from markdorison/tags

Added support for tags.