Merge pull request #2 from atgeirr/master

Multiple changes and advances
collapseJacs(): Don't assume column-major ordering

The 'InnerIterator' is ordering agnostic, so there is no need to
assume that the Jacobians are stored in a particular ordering.
Merge remote-tracking branch 'atgeirr/master'
Merge remote-tracking branch 'atgeirr/master'
Merge remote-tracking branch 'bska/master'