Hint with rule name for suppression

[Bananeweizen]

In the marker properties dialog have a hint showing the internal rule
name. While the human readable name is useful to locate a check in the
configuration dialog, the internal rule name is needed to create
suppression comments.

[Bananeweizen]

This is what it looks like:

[romani]

Does it make sense to make it as label ? To be reat for copy-paste ? Eclipse is very good in idea to let all information displayed be copy-able.

Suppression is done also by id of checkstyle module.

FYI: it is always better to create issue for functional changes and reference it in commit, or reference PR number in commit.

[rnveach]

@Bananeweizen ping

[lkoe]

Roman's question is still open and in my opinion he has a point. There is also sufficient space (horizontal or vertical) to show this information direction.

[romani]

If that take that long, probably it is ok to merge this PR, hint is better than nothing.

[romani]

@Bananeweizen, ping.
Let's finish this PR in any form, some step forward is better than no step at all

[romani]

moved to #173 to merge as is.