Document export to csv with non-ASCII characters as per pull request #70

[Ed McDonagh]

Pull request #70 highlighted an issue with how Excel defaults to open CSV files which renders non-ACSII characters incorrectly by default.

The proposed fix doesn't help, but the comments indicate the change to documentation required.

[Ed McDonagh]

Added instructions for opening csv in Excel with non-ASCII characters. Refs #551

→ <<cset 35bde839a7ab>>

[Ed McDonagh]

Changing a dash to an n-dash. Refs #551

→ <<cset 0d65e832c8f0>>

[Ed McDonagh]

Updating changes. Fixes #551

→ <<cset ede4a6917e3d>>