Merge branch 'stable'

Merge stable into master
Add Website, phone number fields for 1.8.7 Adaptive payments release
Update README.md

just a small fix on the example.
Update to SDK Core v1.5.*
Merge pull request #40 from emersonbroga/patch-1

Update README.md
Update README.md
Updated version number in user agent.

- Fixed composer.json to use generic version
Updated the ReadMe.md to use 2.* instead of *
Merged with Master