Add convenience method in DoubleDouble working on array.
This make the code more readable in GeneralMatrix and Solver.


git-svn-id: https://svn.apache.org/repos/asf/sis/branches/JDK7@1528793 13f79535-47bb-0310-9956-ffa450edef68
Renamed the STRICTFP constant as DISABLED. The old name was giving the impression that
non-STRICTFP calculations were platform-dependant (by analogy with the Java 'strictfp'
keyword), while it was not the case.


git-svn-id: https://svn.apache.org/repos/asf/sis/branches/JDK7@1528795 13f79535-47bb-0310-9956-ffa450edef68