First draft of updating to use Requests library.

There's still plenty to do of course. I'm just committing this now so that I can go and drink beer.
Create LICENCE
Merge remote-tracking branch 'origin/master' into 22-curl2requests
Add licence to composer file.
Clarify that Curl is no longer used. Refs GH#22.
Fix check for existance.
Remove submodule for Curl.
Added debugRequestsConfig() as a replacement for debugCurlConfig() and forwarded the latter to the former. Refs GH#22.
Updated version number to 0.10.0 and changed the README to match new setup. Refs #22.
Merge pull request #25 from hamstar/22-curl2requests

Use Requests library instead of Curl