Merge branch 'master' into labeling_configurable_be
[WIP] last changes identity mapping
remove shapes when text value set and other related changes
improve identity mapping and labeling calculation
extract function for setting graphic attributes on SVG objects
[WIP] identity mappings as submappings
[FIX] move caching to utile and make generic

work around to store instances with specific type
[WIP]

identity mapping for labeling as sub mapping
[FIX] completed identify mapping as submappings

still needs generalization, but should work for text_value
bring text label coloring to d3
extend labeling example
improve labeling and start changing examples
adapting use cases to new non-default labeling
[WIP] towards multiple labels
exclude implicit types assigned by subclass-reasoning
[FIX] quick fix to reenable value mappings

for subclasses when only a superclass is mapped. needs generalization.
for the moment the value mapping map is extended and all subclasses get
the same value as the superclass, ignoring overlapping classes.
[WIP] replace flat by deep labeling
[WIP] some complex labeling works again

labeling on connectors and some other things will still be broken
[WIP] show text, svg and icon labels in parallel
make labeling optional, missing labels will cause error