Fix typo from diff.pysnmf to diffpy.snmf

Author: bobleesj

Diff for: README.rst

@@ -37,7 +37,7 @@
 
 A python package implementing the stretched NMF algorithm.
 
-``diff.pysnmf`` is a Python package that increases the insight one can obtain from a measured series time-dependent signals
+``diffpy.snmf`` is a Python package that increases the insight one can obtain from a measured series time-dependent signals
 through applying the stretched nonnegative matrix factorization (sNMF) and spare stretched nonnegative matrix factorization
 algorithms (ssNMF). The package seeks to answer the question: "What are the structural signals composing my measured signal at
 each moment in time?"