Update README.md

Author: bojunliu0818

README.md

@@ -1,3 +1,18 @@
+testmsm 
+==========
+testmsm is a copy from msmbuilder 3.8.0. You can find the information of msmbuilder 
+in the following. However, msmbuilder has not been updated for a long time.
+testmsm can be used to track changes on msmbuilder and for users to test.
+
+Installation
+------------
+
+The preferred installation mechanism for `testmsm` is with `conda`:
+
+```bash
+$ conda install -c conda-forge testmsm
+```
+
 MSMBuilder
 ==========