Make minimum version compatibility match the introduction of legacycustomsearches

See merge request !106

Declare dependency on legacycustomsearches

See merge request !105

Provides ability to set the file name for the CSV export download, instead of using randomly generated file name

See merge request !104

When using the CSV export, the web browser can cache the downloaded CSV file...

See merge request !103

PROJ-2313 Provides ability to set the file name for the CSV export download, instead of using randomly generated file name

When using the CSV export, the web browser can cache the downloaded CSV file preventing new versions of the CSV to be downloaded. Fixes !107

TextFromFieldsOutputHandler: fallback template, other minor code changes

See merge request !102