Update README.md

Corrected filename reference
Improved IDE.md formatting
Merge pull request #17 from dhoepelman/patch-1

Update README.md
Merge pull request #18 from dhoepelman/patch-2

Improved IDE.md formatting
Changed java version to 1.7 in order to support newest features.
Added Guava (collections) and Mockito (testing/mocking)
Used BidiMap from Guava instead of from the project. Removed project's
BidiMap-implementation.
Used Guava's String joiner instead of StringUtils' one.