examples/python: Add/update shebang line

Added/updated the shebang line on all python examples with:

Also chmod +x a few of the python examples.

Signed-off-by: Noel Eck <noel.eck@intel.com>

examples/python/sensortemplate.py

@@ -1,3 +1,4 @@
+#!/usr/bin/env python
 # The MIT License (MIT)
 #
 # Author: Your Full Name <your@email.address>