fix bug when the same dataset from two different locations is loaded
fix for non-disjoint clustering
add mixture handling for pc descriptors
fix cluster sorting, add external 3d computation, cache mixture-pcs in different fiel, fix colors for nominal features, add include constraint for command line feature selection
large commit

change:
* add filter concept
* one can remove / export un-selected compounds
* improved 2d icon renderering

small change:
* openbabel 3d for csvs is computed form smiles/inchi instead from cdk-2d-sdf
* more messages
* rendering of sets: null is ignored for coloring
* mixture handling can be switched on via command line, results are cache in own file

fix:
* domain is stored per dataset (this may cause errors when multiple datasets share common nominal features)
* features computation is repeated if 3d structure is computed by now

rewrite:
* do not store clusters in seperate files
* cache is now independent from relative class path
* cached files are stored in .ches-mapper/cache
* make caching faster
app-domain - 3d-builder - more

3dbuilder : use orig 2d-sdf instead of the one from cdk
3dbuilder : openbabel: do not compute 3d for mixtures
3dbuilder : sdf-importer (hidden)
3dembedder : get-feature-distance-matrix
extension : large-data-mode
extension : app-domain-probs (hidden)
cdk-icons : option for translucency
fix: set compound index when there are no props
optimization: load in background
rewrite: mapped-dataset is stored globally
fix: use same screen for loading dialog as for wizard
refactoring: do not auto-load all images in image loader
hide-translucent

extend : hide/translucent/solid
refactor : screen index is stored globally
fix 3d alignment of clusters when cached
fix prop app-domain computation
reduce screenshot size
provide numericalized data as seperate function (for SOMs, not used at the moment)
show mean instead of median
re-order descriptors
add smarts view dialog
action text for sort and filter dialog