Initial spec/class for SendGridApi

Class is loading and Specs are now properly generating... and passing!
- Edits composer.json: updates psr-4 to `"ErikAybar\\SendGridWeb\\": "src/ErikAybar/SendGridWeb"`
    - phpspec was not seeing already created classes using the previous `"src"` path
    - Updates project name
- Adds phpspec.yml
- Specs
    - it_is_initializable
    - it_should_have_a_base_url
Still experimenting with Prophecy objects etc... - WIP

Test(s) passing/broken
- PHPSpec recognizing that classes don't exist. Not requesting to create them
- See here: http://sylius.readthedocs.org/en/latest/contributing/code/bdd.html
Updates README
Merge pull request #1 from erikthedeveloper/develop

Develop -  WIP