Add a denoise filter
Fix temperature calibration
Tidy up some files
Improve MCIR

Add the ability to open a map overlay generated by wxmap (still unstable)
Remove the ability to turn off calibration
Add MCIR images
From now on large changes to neaten up the codebase will be taking place

Also made some floating-point math more explicit

Improved commenting in dsp.c
Updated copyright notices
Code tidy up in some parts

This fixes the build.  It looks like the tree was forked during
some incomplete work :(

new dsp code
ngvi test

-cleaning dsp code

-Cleaning pll

-new resample filter
-accept different sampling rates