Make global TUS capability configurable

[PVince81]

Added global TUS capability in the config structure.
Added config switches for the advertised max chunk size and http method
override.

• adjust value semantics for tus_support and max_chunk_size (see original ticket)
• add config switch to disable "tus_support" completely
• add changelog entry

Requires cs3org/reva#775 to work.

[update-docs]

Thanks for opening this pull request! The maintainers of this repository would appreciate it if you would create a changelog item based on your changes.

[PVince81]

• fix tus disable switch: somehow env var doesn't disable it: export REVA_FRONTEND_UPLOAD_DISABLE_TUS=true => the option was set correctly, the problem is that there was no option in reva for that, added in Add option to disable TUS on OC layer cs3org/reva#791

• check if we should also disable the TUS implementation as reva might have switches for that already => Add option to disable TUS on OC layer cs3org/reva#791

• REQUIRES Add option to disable TUS on OC layer cs3org/reva#791 for the new disable_tus options on OC layer

[ownclouders]

Here is an overview of what got changed by this pull request:

Complexity increasing per file
==============================
- pkg/command/frontend.go  1
         

See the complete overview on Codacy

[refs]

@PVince81 merge or do you want to update reva dependency on the PR?

[PVince81]

@refs I usually prefer to update reva separately

[refs]

@refs I usually prefer to update reva separately

good, let's keep it that way 👍