"Validation errors" layer should be added below data layers

[mkoniecz]

When I create "Validation errors" layer by validating some OSM data, it is put at the top of the stack.

Once I use "Zoom to problem" the line is obscured by marking line with very wide line - see attachment default.png

Switching layers makes possible to again see marked way - see attachment better.png

related to #3529

Maybe it would be better fixing by changing complete fill into something more discreet (half transparent fill)?

Repository Root: http://josm.openstreetmap.de/svn
Build-Date: 2013-11-15 02:34:58
Last Changed Author: Don-vip
Revision: 6386
Repository UUID: 0c6e7542-c601-0410-84e7-c038aed88b3b
URL: http://josm.openstreetmap.de/svn/trunk
Last Changed Date: 2013-11-15 02:00:02 +0100 (Fri, 15 Nov 2013)
Last Changed Rev: 6386

Identification: JOSM/1.5 (6386 en_GB) Windows 7 32-Bit
Memory Usage: 247 MB / 247 MB (81 MB allocated, but free)
Java version: 1.7.0_45, Oracle Corporation, Java HotSpot(TM) Client VM
Dataset consistency test: No problems found

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