HPCC-10095 Help Icon Issues

Changed Icon from a (?).
Added About dialog.

Fixes HPCC-10095

Signed-off-by: Gordon Smith <gordon.smith@lexisnexis.com>
Merge pull request #4893 from GordonSmith/HPCC-10095_HelpIconIssues

HPCC-10095 Help Icon Issues

Reviewed-By: Miguel Vazquez <miguel.vazquez@lexisnexis.com>
Reviewed-By: Richard Chapman <rchapman@hpccsystems.com>