Merge pull request screwdriver-cd#5 from screwdriver-cd/eslint-update

Update ESLint to latest

Merge pull request screwdriver-cd#2 from screwdriver-cd/MajorVersion

Adding Matrix, Environment, Image, and Workflow

Merge pull request #1 from screwdriver-cd/FirstPass

Parsing the most basic screwdriver.yaml parsing (supports just steps)