Merge pull request #25 from rolk/025_distrib

Fix bug in reporting of system release (on RHEL 6.4)
Fix issue 27, bug in call to viscosity().
Merge pull request #28 from atgeirr/issue-027-fix

Fix bug in call to viscosity().
check for the C++-2011 'auto' keyword.

It seems like the corresponding FindCXX11Features.cmake file
was not updated for this module.
make the c++-2011 feature set of GCC 4.4 mandatory

we now produce an error even if the module in question does not
actually use some of these features.