remove don't preserve option from LogPreservingThreadFactory
fix UTF-8 BOM logic test
Fix for Bug NMS-6855

Can't modify an existing systemDef through Vaddin UI for Data Collection
Groups.

Other enhancements have been applied with this commit:

1) Fixing minor typo error on EditorToolbar.java

2) Only allow to add/remove MibObjs from groups if storeByGroup is
disabled and the user is modifying an existing datacollection-group.
add a null check for null svg file