pw_cli: Add envparse module

This change adds a Python module which implements an environment
variable parser that allows defining and typing environment variables
for a Python program.

Change-Id: Icda61c8dabcf4e4bc6902707f6ebed9c50d31d71
diff --git a/.pylintrc b/.pylintrc
index 3445b61..816add7 100644
--- a/.pylintrc
+++ b/.pylintrc
@@ -299,6 +299,7 @@
            ex,
            fd,
            Run,
+           T,
            _
 
 # Include a hint for the correct naming format with invalid-name.