Support exporting tables

[kgodey]

Mathesar's UI should support exporting tables (and explorations) in common formats.

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If you'd like us to build this feature, please comment below with more details about how you plan to use this functionality.

[jeromeperez]

It should be very interesting for my user to have possibility to export data and exploration to show their work to other people without access to database

[jeromeperez]

in my case a csv and/or tsv format are better format.
The share feature is not interesting in my case because searchers have to work on data i send with R, python or other software

[kgodey]

Thank you @jeromeperez!

[jeromeperez]

This feature of exporting data or exploration in a tsv file is very important for my searchers, i hope you will add it

[kgodey]

This is high on our priority list, but we'll need to finish our current backend and permissions refactor before we will be able to work on this.

[jeromeperez]

i can wait ;-)