Added Async IO support for output file of betas to improve performance.

git-svn-id: svn://svn.r-forge.r-project.org/svnroot/genabel@1617 edb9625f-4e0d-4859-8d74-9fd3b1da38cb
Unsigned int error Fixed when printing to screen.

git-svn-id: svn://svn.r-forge.r-project.org/svnroot/genabel@1618 edb9625f-4e0d-4859-8d74-9fd3b1da38cb