Sthor/api helper updates

[steinitzu]

Tell us what you do here

Adding a few changes to the rest api source:

• Support json path in "next url" paginatior
• Add "cursor" paginator
• Use "parse_native_value" instead of requiring args in init for the standard auth classes, they were not reading from config before
• Uppercase HTTP method names as is standard

I'm currently testing it out with openapi gen, so might add some more

[rudolfix]

@steinitzu also if you could merge the latest changes, it would be good