FEATURE: Improve wording "Upload documents"

[tillprochaska]

Is your feature request related to a problem? Please describe. We currently use "Upload documents" as a label to upload files in investigations. Users have been confused about this in the past, because they assumed this would only allow them to upload actual documents like Word or PDF files (and not images, spreadsheets etc.). We should consider using different wording.

If we decide to change the wording we should also check other features in Aleph as well as FtM to ensure we use terms consistently.

Describe the solution you'd like Not sure yet, maybe "Upload files".

Describe alternatives you've considered None

Additional context

[tillprochaska]

UI	Description
	This re-ingests all files that users have uploaded, including images, audios, etc.
	This selects only document-like files (i.e. it excludes images, audios, etc.)
	This allows users to upload any type of file, including images, audios, etc.
	Same
	This shows only document-like files (i.e. it excludes images, audios, etc.)
	The file listing includes non-document files like images, audios. However, the number of documents in the badge doesn’t include non-document files.