Add section on DTW

[nipunbatra]

Reference: http://rdatamining.wordpress.com/2011/08/23/time-series-analysis-and-mining-with-r/

Using this and rpy2, one can do the following:

• DTW to compare different sequences (maybe 2 different days of appliance usage)
• warp and align
• Produce a distance and path matrix
• Feed that into hcluster or some other clustering function in R or Python which accepts distance as input

Currently a lot of clarity is required in initial step.

[nipunbatra]

Added a test financial data here http://nipunbatra.wordpress.com/2013/06/09/dynamic-time-warping-using-rpy-and-python/

As such need more clarity about the concept.