Fix key-value writing: no space allowed after ':=' identifier

[ihnorton]

This was changed in #57

but per the NRRD documentation: http://teem.sourceforge.net/nrrd/format.html#general.2

"""
Each of the ":=" lines specifies a key/value pair in the nrrd. These can appear in NRRD0002 (and higher version) files, but not NRRD0001 files. The key and value strings are delimited by the first ":=" to appear on the line: any spaces before or after ":=" are assumed part of the key or value, respectively.
"""

[codecov-io]

Codecov Report

Merging #69 into master will not change coverage.
The diff coverage is 100%.

@@           Coverage Diff           @@
##           master      #69   +/-   ##
=======================================
  Coverage   87.39%   87.39%           
=======================================
  Files           6        6           
  Lines         357      357           
  Branches      114      114           
=======================================
  Hits          312      312           
  Misses         22       22           
  Partials       23       23

Impacted Files	Coverage Δ
nrrd/writer.py	87.17% <100%> (ø)	⬆️

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[addisonElliott]

Good catch! 👍

Do you think we should not remove whitespace from the key/value pairs when reading NRRD files? Personally, I lean towards no because I can't think of any useful reason of having whitespace in the value.

And, when I merge this in (I'll try to tonight), I'll probably wait to release the next version unless you really need these changes now. Hopefully a few more PRs come in soon and I can make a larger release.

[ihnorton]

Do you think we should not remove whitespace from the key/value pairs when reading NRRD files? Personally, I lean towards no because I can't think of any useful reason of having whitespace in the value.

Agree, try to stick to spec when possible. I think some readers de-facto allow whitespace after the := (e.g. if using >> operator to read whitespace-separated values in C++) but some software we use does not.

[tashrifbillah]

Hi @addisonElliott , can we get a release incorporating @ihnorton 's latest changes?
The release 0.3.4 does not have Isaiah's latest commit.

[addisonElliott]

Sure, I'll release a new version tonight.

[addisonElliott]

v0.3.5 Released! 🎉

[tashrifbillah]

Thanks @addisonElliott . We have also switched to the release version.