CHANGELOG

2021-05-25 Release 0.6
	- add support for object-style JSON
	- remove Source.getMatchingColumns()
	- add Source.getColumnIndex() and Source.getColumnIndices()
	- many speed optimisations

2021-05-07 Release 0.5
	- updated to eliminate complaints from ESLint
	- added getRawValues() method to get all the values in a dataset column (not just unique)

2021-04-27 Release 0.4.1
	- bug fix for reverse in sort filter

2021-04-27 Release 0.4
	- added standalone hxl-parse-hashtag.js module for visualisations, etc
	- added SortFilter and PreviewFilter, and corresponding hxl.Source.sort() and hxl.Source.preview() methods
	- added hxl.Source.sum() aggregation method

2019-03-29 Release 0.3
	- added hxl.Source.exportArray() to export data as an array
	  including hashtags (and optionally, headers)
	- fix bug with null columns when there's no hashtag
	- start adding data typing methods
	- add support for wildcard tag patterns (e.g. "#*+f")
	- add support for absolute tag patterns (e.g. "#affected+children")
	- make hashtag specs and tag patterns case insensitive
	- added matchList() method to TagPattern class
	- add hxl.match() and hxl.matchList() convenience functions for
	  matching tag patterns