Rename 'redis.py' to 'redis_monitoring.py' to avoid conflict

Ganglia appends the metric module path ('/usr/lib/ganglia/python_modules') to
PYTHONPATH, meaning modules in the standard system location take precedence
over metric modules in cases where the names conflict. This patch renames the
metric module to 'redis_monitoring' to avoid conflict with pyredis.

Bug: 52540
Change-Id: I480198ce08043816ccfd187be7a2c1493ed34dce
Merge "Rename 'redis.py' to 'redis_monitoring.py' to avoid conflict" into production