Issues with Custom Storage location doc

[kelshmo]

• I don't know how to interpret "If your bucket is set for read-write access, files can be added to the bucket using the standard Synapse interface (web or programmatic)."
• Remove out-of-date images and link to Uploading a File as well as documentation for uploading a file in all clients
• grammatical error in the first paragraph
• Update reference to buttons in the web here and here
• Make explicit that storage can be modified on projects and folders
• Can this operation work on a folder parent id as well?

[allaway]

Additional issues that I have run into:

-The docs state that an owner.txtfile is required for read-write access to a bucket, but from what I can tell this is also required to be able to link up a read-only bucket. Reorganizing this section would likely fix a lot of confusion (and would have saved me an hour of trying to figure out why I couldn't link up a read-only bucket)
-The docs do not describe how to retrieve the storageLocationId

[allaway]

-several snippets do not specify where the toJSON function is coming from. Should specify rjson::toJSON as JSON produced with jsonlite::toJSON without the auto_unbox = T parameter set will cause synapser to throw an error

[allaway]

another issue: docs don't describe how to change a storage location programmatically. This is not as simple as re running the "https://docs.synapse.org/articles/custom_storage_location.html#set-s3-bucket-as-upload-location" snippet, because if an upload location already exists, synapse throws this error:

Error in value[3L] : 400 Client Error:
A project setting of type 'upload' for project syn11727056 already exists.

So there must be a need to remove the project setting but it's not clear how to do that.

[allaway]

Looking through the API docs, this is how I ended up removing the project setting so that I can add a new one:

projectSettingsId <- synRestGET(glue::glue('/projectSettings/{parentId}/type/upload'))$id
synRestDELETE(glue::glue("/projectSettings/{projectSettingsId}"))