Note about RestfulService SSL verification in upgrading guide
BUGFIX: fixed file icon for uppercase file extensions
Merge pull request #1257 from Zauberfisch/3.1.0-beta2

BUGFIX: fixed file icon for uppercase file extensions
Merge remote-tracking branch 'origin/3.1.0-beta2' into 3.1
API: refactored Hierachy class to use new DataObject::get() syntax
API: removed broken & unused method Hierachy->partialTreeAsUL()