Changelog for pandoc-plot-0.6.1.0

Change log

New toolkits:

Other changes:

The determination of which figures to re-render or not has been improved. For example, changing the caption will not trigger a re-render of a figure anymore.
pandoc-plot will look for executables more thoroughly.
pandoc-plot toolkits will now show the exact executable that is being used, if possible.
Added a check when running the filter that the Pandoc version is at least 2.8. This is easier to understand that the default Pandoc warning on API incompatibility.
Added the ability to write the example configuration to an arbitrary file using pandoc-plot write-example-config.
Added the possibility to specify the configuration file via metadata. For example, in Markdown:
```
---
title: My document
author: John Doe
plot-configuration: /path/to/file.yml
---     
```

or on the command line:

pandoc --filter pandoc-plot -M plot-configuration=/path/to/file.yml ...

Added the ability to specify configuration file to the pandoc-plot clean and pandoc-plot toolkits commands.

The pandoc-plot executable will now process documents in parallel. This should dramatically speed up processing of large documents with lots of figures. This happens automatically through the function plotTransform.
Added a benchmarking suite.
Added defaultConfiguration so that people don't have to install the data-default package to get access to default configuration values.
Added a check for the matplotlib toolkit, preventing users from using matplotlib.pyplot.show in figures. This would halt pandoc-plot.

Fixed an issue where the pandoc-plot executable could not be built outside of its git repository.

Updated documentation.
Added a --full-version flag to the executable, which includes which version of pandoc/pandoc-types was used, as well as the git revision.
Added the clean command to the executable. This can be used to clean-up output files produced by pandoc-plot.
Changed the flag --write-example-config to the command write-example-config.
Added the top-level function cleanOutputDir to clean output of pandoc-plot. This is only accessible if pandoc-plot is used as a library.
Added a distinction between failure to render a figure because of a mistake, and failing to render a figure because the toolkit is not installed. pandoc-plot will give better error messages in the latter case.

Added more examples.
Added MacOS binaries built via Azure pipelines.
BREAKING CHANGE: Parsing captions based on source file was not working. Captions format can be specified in the configuration file. This unfortunately changes the type signature of a few high-level functions.

Added support for gnuplot.
Added more tests for all toolkits.
Fixed an issue where the package could not be installed because a source file was not included in the cabal file.