Tiling script

This MR is a first step to provide a tiling scan feature for BM18 (or other fullfiled tomo beamline)

It provides

• A tiling runner (based on mesh scans)
• A tiling sequence (including dark, flat, tiling proj)
• A connector to read back data from acquired data (tomo.newtomo.helpers.tiling_helper) (@tvincent)
• Including a Qt script to check the result
• Unittest including writer + icat + detector in HDF5 (if you like to check @denolf)

Example

python scripts/show_tiling_scan.py /tmp_14_days/valls/tiling_2021-11-03/id002111_sample.h5 sample_0001_1.1

Which is a tiling of many 128×128 images