Add Override annotation

It can be very helpful to avoid mistakes override-vs-overload. Especially when refactoring.
Avoid generics in equality check assertions
Add ThrowableAssert#hasCauseInstanceOf assertion - Issue #19
Add ThrowableAssert#hasCauseExactlyInstanceOf assertion - Issue #19
Add ThrowableAssert#hasRootCauseInstanceOf assertion - Issue #19
Remove an occurrence to FEST in Javadoc.
Add ThrowableAssert#hasRootCauseExactlyInstanceOf assertion - Issue #19
Allow to pass any Throwable

And also fix a typo
Merge pull request #80 from ash2k/argument-fix

Allow to pass any Throwable instead of Exception only
Merge pull request #78 from ash2k/equals-without-generics

Equals without generics
Fixes #19 : Add cause assertions to ThrowableAssert (minor refactoring)
Merge branch 'throwable-cause'