Issue #389: removing old LPF code

Removed the following unused / antiquated files: 
- examples/prediction/Cleanup.py
- examples/prediction/RunExperiment.py
- py/nupic/frameworks/predictions/*
- py/regions/CLARegion.py
- py/regions/CLARegionSimple.py

Removed 'tests/integration/py2/nupic/engine/network_serialization_test.py' because the same functionality is tested in 'tests/integration/py2/nupic/opf/opf_region_test.py'.

Removed unused import 'from nupic.frameworks.prediction import utils' from: 
- py/nupic/data/aggregator.py
-py/nupic/data/sorter.py

Removed several tests comparing LPF and OPF from 'tests/integration/py2/nupic/opf/opf_region_test.py'
Also removed imports and extra methods used by LPF.

Updated antiquated import from 'py/regions/RecordSensor': 'from nupic.framework.prediction.sources import FileSource'
Updated comment in 'py/regions/RecordSensor' to reflect updated import.

Updated a test in 'tests/unit/py2/nupic/engine/network_test.py' to not use LPF code.