Add section about Dependency Installation to README.md
Add Contributing section to README.md
Capitalisation improvements.
Use "Development Dependencies" instead of "Dependencies" for less confusion.

There are currently no production dependencies.
Merge pull request #316 from bantu/readme-update

Add "Installing Dependencies" and "Contributing" sections to README.md

* bantu/readme-update:
  Use "Development Dependencies" instead of "Dependencies" for less confusion.
  Capitalisation improvements.
  Add Contributing section to README.md
  Add section about Dependency Installation to README.md
Merge branch 'master' into php5

* master:
  Use "Development Dependencies" instead of "Dependencies" for less confusion.
  Capitalisation improvements.
  Add Contributing section to README.md
  Add section about Dependency Installation to README.md