ARM

Changes were made so that if an FIR decimate is used on an ARM environment, firdecim_xxx_executeNEON can be called. This will call Dotprod_executeNEON which will then call dotprod_NEON which uses NEON assembly (from dotprod.s) and NEON intrinsics. This makes the filter perform over 50% more efficiently. FMDemod was also changed so that if it is running an ARM evironment, the pre and post filters won't be used to increase execution speed.