Help wanted: Additional convolution functions

[liebharc]

The lib comes so far with two convolution functions: http://liebharc.github.io/basic_dsp/basic_dsp/conv_types/index.html
There are a lot more common convolution functions and it would be nice to have some of them. To my mind comes right now root raised cosine, gauss, triang and square. But there are for sure more than that.

The following files likely need to be touched:

• conv_types.rs
• facade32.rs
• facade64.rs can be created with a script

The task would include:

• Discuss which convolution functions should be part of the lib
• Implementation
• Documentation
• Test