Low pass filter API tweak
Merge branch 'master' of https://github.com/eile/vmmlib

Conflicts:
	include/vmmlib/lowpass_filter.hpp
Merge branch 'master' of https://github.com/VMML/vmmlib
Low pass filter: cache filtered value, implement more convenient accessors
Merge pull request #37 from eile/master

low pass filter improvements