Refactor ContentView.path and related code

Reduce the amount of duplicate code used to implement method `ContentView.path`.
Make the relevant tests easier to read, and alphabetically sort the relevant
test's data.
Manifests-api: Added few tests related to manifests

Added the below tests:
* test_positive_create_1
* test_positive_delete_1
* test_negative_create_1

Manifests-API tests: Fixed the variable names.
Merge pull request #1367 from kbidarkar/manifest-api

Manifests-api: Added few tests related to manifests
Merge pull request #1368 from Ichimonji10/content-view-path

Refactor ContentView.path and related code
Improve requests wrapper

Make the client does not set the content-type header when doing file
uploads.
Does not call json.dumps if data is None. None means that does not want
to send any data, but if the dumps is called it will be converted to
equivalent null on JavaScript and this make Satellite server break.