Provided RestxSpecTests.specsAsParametersIn()
to ease creation of Parameterized tests based on specs
+ Used this method to automatically reference specs in SessionsTest
Simplified HelloResourceSpecTest
by using @RunWith(RestxSpecTestsRunner.class) & @FindSpecsIn

I kept (in comment), the RestxSpecRule usage, in order to make the developper
conscious of the *manual* way to executing spec tests
Merge pull request #43 from fcamblor/specs-based-test-refacto

Some minor improvements in the way spec tests were written