API-16: Pre-release dev branch for support for FS style upload workflow (#34)

[Arpit-Sharma-USC]

This is a pre-release PR to be merged when the SDKs are tested against staging when API-55 is resolved.

• new FS upload

• new fs upload workflow

• remove old aws s3 dependencies

• tests

• tests, docs, readme fix

• documentation comments and code cleanup

• minor test fixes and more formatting

• suggested changes and formatting

-get ride of state variables

• cleanup RequestHandler

• format tests

• suggested changes- part 1

• remove fileID and correlationId return from uploadFile

• clean up doc comments

• clean up fileSha256 usage -revert AbstractRequestHandler (no raw response needed anymore)

• add brandId non-null check

• test for invalid brandId

• suggested changes - part 2

• clean the header updation a little

• suggested changes - 1

• change filePath from a request param to a method param

• recycle code in tests

• fix saveMediaAsync for mediaId and brandId

• fix tests per the changes

• update sample and readme with new uploadFileAsync usage

• comments to save media for understanding

• suggested changes - 2

• prune upload intent for sdks

• remove server-ignored form_params