Corrections to help text in admin group settings

Due to the functionality improvements in the admin group settings fieldset #504202: 'Unpublished' title and desc entry fields on admin form I believe some of the help text needs to be altered to keep them in line with the validation now being done. Also changes in #563606: Show unclassified group description even when group title is blank require slight adjustments to the help text.

1. For the Unclassified description, I removed the text which says 'If this group has no title this text will not be shown either' to make it consistent with the proposed change in behaviour in weblinks_unclassed()
2. For the Unpublished Title this cannot now be blank, so the text needs to be changed (currently it says it can be blank). Also this currently says 'unclassified' when it should say 'unpublished'.
3. For the Unpublished Description, I have removed the text which says it wont be displayed if the title is blank - because the title cannot now be blank.
4. As a general point - is there any need to say at the end of each line 'It will not be translated'? My understanding is that user or admin input text is rarely translated, and the guide for t() says explicitly not do it, so I do not think that any admin would expect this text to be translated.

The attached screen grabs show before and after, and the patch is rolled against dev 08-29. If you'd like bits of this changed, or want to implement part of it, just let me know and I'll re-roll.

Jonathan