Try to remove HDF5 files that cannot be fully written due to an exception

One amended source file:
blimpy/io/hdf_writer.py

Clarify HDF5 b-tree errors

Catch corrupt B-tree in an HDF5 file with a clearer message. The corrupt files are caused by crashes during HDF5 file creation.

A betterfix to issue #226

Merge pull request #229 from texadactyl/master

A betterfix to issue #226.

Diagnose false and broken HDF5 files

The io/hdf_reader.py was updated and a new stand-alone utility, h5diag, was introduced.

New signal_processing source file, "dedoppler.py"

This is the first in a planned series of signal processing functions for blimpy.
In this release:

• blimpy/signal_processing/dedoppler.py - first dedoppler function
• tests/test_dedoppler.py - test for dedoppler.py and usage sample

New utility, stix

LOFAR folks have some really huge Filterbank files E.g. 140 GB. Today's blimpy cannot plot them because it tries to get the whole data matrix into memory first.

New approach: Slice them into manageable sized sticks by fine-channel frequency subrange and plot each one separately. Optionally, concatenate all of the generated PNG files horizontally or vertically into one PNG.

New utility function: stix

stix -h
usage: stix [-h] [--plot_dir PLOT_DIR] [--source_name SOURCE_NAME] [--stitch {n,v,h}] [--dpi DPI] [--width WIDTH] [--height HEIGHT] input_file chunk_count

Make waterfall plots from a single huge file, viewed from top to bottom.

positional arguments:
  input_file            List of files to plot
  chunk_count           Count of same-sized frequency chunks

optional arguments:
  -h, --help            show this help message and exit
  --plot_dir PLOT_DIR, -p PLOT_DIR
                        Directory to receive the plot (.png). Default: current directory.
  --source_name SOURCE_NAME, -n SOURCE_NAME
                        Source name to override the header field. Default: None.
  --stitch {n,v,h}, -s {n,v,h}
                        Stitch files: n(no stitching), v(vertical), or h(horizontal). Default: n.
  --dpi DPI, -d DPI     Single image file dots per inch. Default: 200.
  --width WIDTH, -w WIDTH
                        Single image file image width in inches. Default: 10.
  --height HEIGHT, -t HEIGHT
                        Single image file image height in inches. Default: 8.

Get fil2h5 to support very large filterbank files

Fixed issue #218

Fix issue #212

Waterfall.blank_dc() caused numpy "RuntimeWarning: Mean of empty slice" when the ratio between the number of fine channels to the number of coarse channels was < 5. This is a boundary case.

Release 2.0.17.1 crashed [?}

Release 2.0.17.1: Undetected editing mistake in blimpy/init.py led to a missing value for version detected in turbo_seti.
Blimpy operations are unaffected.

For some unknown reason, release 2.0.17.1 crashed. So, release 2.0.17.2 hopes to rectify that.

Emergency release to 2.0.17

Undetected editing mistake in blimpy/init.py led to a missing value for version detected in turbo_seti.
Blimpy operations are unaffected.