Adding visual indicators to column sorting in HTML output
Adding visual indicators to column sorting in HTML output

- Unicode arrows added to the end of text on a sorted column
- Sorted column header always have grey background

https://bitbucket.org/ned/coveragepy/issues/298

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branch : issues-298

nedbat/coveragepy,hugovk/coveragepy,blueyed/coveragepy,nedbat/coveragepy,hugovk/coveragepy,blueyed/coveragepy,hugovk/coveragepy,blueyed/coveragepy,blueyed/coveragepy,blueyed/coveragepy,nedbat/coveragepy,hugovk/coveragepy,nedbat/coveragepy,nedbat/coveragepy,hugovk/coveragepy