Dclab

- fix: slicing of non-scalar features for hierarchy children (128)
- fix: passing a directory to the CLI tdms2rtdc did not work
- enh: support slicing of non-scalar features for DCOR data (132)
- enh: support slicing of the contour feature for HDF5 data (132)
- enh: support slicing of LazyContour for contour AncillaryFeature (132)
- enh: minor optimizations of the DCOR format
- ref: raise NotImplementedError for futile attempts to slice the image,
contour, or mask features for .tdms data (132)
- ref: cleanup CLI code
- tests: increase coverage of CLI (116)

- enh: introduce user-defined "user" configuration section (125)
- scripts: refactor fem2lutiso_std.py and fem2iso_volume.py so that
model-specific post-processing is done in hooks named after the FEM
identifier, e.g. fem_hooks/LE-2D-FEM-19.py (90)
- docs: new LUT data version 10.6084/m9.figshare.12155064.v3
- ref: minor code cleanup

- feat: introduce user-defined plugin features (105)
- fix: dclab-verify-dataset now also prints other errors it encounters
- fix: installing the "lmer" R package failed, because "statmod" was not
installed
- fix: correct data types for "fluorescence:sample rate",
"imaging: roi position x", and "imaging: roi position y" (124)
- enh: support new .rtdc attribute "online_contour:bg empty" which is
True when the online background image is computed only from frames
that do not contain any events (124)
- enh: `AncillaryFeature` now populates other ancillary features when they
share the same method (104)
- enh: dclab-verify-dataset now returns a non-zero exit code if there
were errors, alerts, or violations (120)
- ref: streamlined dataset check function for missing meta data keys

- fix: add "chip identifier" to "setup" configuration section and
make it optional during dataset checks (109)
- fix: ignore empty metadata strings (partly 109); removed the
`check_metadata_empty_string` check function because it does
not apply anymore

- fix: some datasets with unknown feature names could not be
opened (AssertionError regression in 0.33.1)
- fix: workaround for sporadic JSONDecodeError when accessing DCOR
- ref: cleanup cli.py
- ref: cleanup util.py and deprecate `hash_class` argument in
`hashfile`

- fix: add dataset check for wrong medium written to .rtdc file
by Shape-In
- fix: filters were ignored when exporting trace data to hdf5 (112)
- enh: allow to set ICue identifier for integrity checking
- ref: code cleanup in export.py