Changed the Q-statistics and ARCH-LM tests on estimated model to weighted tests of Fisher and Gallagher (2012).

git-svn-id: svn://svn.r-forge.r-project.org/svnroot/teatime@91 edb9625f-4e0d-4859-8d74-9fd3b1da38cb
git-svn-id: svn://svn.r-forge.r-project.org/svnroot/teatime@92 edb9625f-4e0d-4859-8d74-9fd3b1da38cb
git-svn-id: svn://svn.r-forge.r-project.org/svnroot/teatime@93 edb9625f-4e0d-4859-8d74-9fd3b1da38cb