volk: naming error between orc file name and kernel name.

Fixes bug #583.
volk: explicitly casting tolerance to float or unsigned int for passing to fcpmare or icompare in QA tests.

On ARMs, passing tol as a float to icompare that expects an unsigned int caused improper casting. Fixes bug #582.
blocks: loosen restriction on damping factor in control_loop class.
Merge branch 'maint'