mathias/hum — pull request #11 by triss (2014-12-14 16:05:52+00:00)
Title: Added helper functions for constructing and triggering envelopes

See example in README for details of how to operate exponential-env, linear-env and step-env behave similarly.

trigger-env works as follows fro envelopes with stepped linear and exponential segments:
```clojure
(hum/trigger-env vcf :frequency
[[hum/set-value-at 100 1]
[hum/exponential-fade 1000 3]
[hum/linear-fade 100 5]]
(hum/curr-time ctx))
```