improve progess bar of validator

[Klumbumbus]

1. validate a larger data set
2. see how the test "Tag checker (MapCSS based)" takes by far the longest time of all the test
3. during this test you see no progess in the progress bar
4. for better user feedback it would be nice to print all the single mapcss based tests separately
5. --> more "fluent" validation progress

This would count for all core tests and all active Rules

Build-Date:2016-10-14 21:42:43
Revision:11128
Is-Local-Build:true

Identification: JOSM/1.5 (11128 SVN en) Windows 7 32-Bit
Memory Usage: 247 MB / 247 MB (0 MB allocated, but free)
Java version: 1.8.0_102-b14, Oracle Corporation, Java HotSpot(TM) Client VM
Screen: \Display0 1680x1050
Maximum Screen Size: 1680x1050
Dataset consistency test: No problems found