Corrected date format in Tracing instrument , #3200
YYYYMM to YYYY-MM, adding input mask to help enforce this format.
Closes Bug #3200. Added capability of input mask to take differing
placeholders.
[source: https://github.com/digitalBush/jquery.maskedinput/pull/56/files]
Merge remote-tracking branch 'origin/bug_3200' into bug_3200