convert.h: Remove unneeded volatile keyword for constant global values.
As those global values are never changed and serve as simple constant, the volatile keyword is not needed here. As a plus, it fixes the linkage errors encountered on newer gcc versions and therefore Closes: #25
I thought about adding additional inline functions with shifting operations or switch-cases but i assumed that the code is intended to work most effectively. So I kept the current flow.
convert.h: Remove unneeded volatile keyword for constant global values. As those global values are never changed and serve as simple constant, the volatile keyword is not needed here. As a plus, it fixes the linkage errors encountered on newer gcc versions and therefore Closes: #25