Query results sorting

[Lokomojo]

Thank you for implementing the query filter in #89.

However, it's not possible to click the column headers to sort the result set.

This is a very useful feature in Heidi!

[ragnar-lodbrok]

Sorting is implemented in devel branch if you want to use it before next release.

[ragnar-lodbrok]

@TomMettam Thanks for feedback, please check the latest release (only Table data is done for now).

[Lokomojo]

Thanks - the query data sorting is the most needed from my perspective though. Loving how this software is evolving, it's more stable than Heidi and more usable than any other gui on linux!

[ragnar-lodbrok]

Available in 0.4.17 (single-column only).