Fixed timestamp string format.

This fixes the error message 'invalid date' when displaying the data on the map when the app is running.
Fixed args order to match new GCE interface
User can now choose to extract elevation data from GPX file.

The user can now indicate that the GPX file to parse contains elevation information and wants it to be included
in the .csv output file.
Elevation data can now be extracted from GPX files.

The -e option now indicates the converter that the GPX file contains elevation information, so it includes
that data in the output .csv file.
Added option to convert elevation data to meters.

The elevation data that is going to be used by the GCE should be in meters. If the GPX file elevation data is
in feet, then the user can select this option to convert it automatically.
Reworded feet-to-meters conversion option description.
Added verbose debug lines for altitude options usage.
Fixed failing test
Fixed failing test (no, really)

Changed assertion to check if both floats are equal up to 6 decimal places.
Altitude data can now be used when generating anomaly scores.

The script geospatial_anomaly.py (invoked by run.py) uses altitude data to calculate anomaly scores if it's present
in the input file.
Tidying up the code
Merge pull request #38 from hernan-erasmo/issue-36-conform-to-GCE-update

Changes in demo app to take advantage of GCE enhancements.