Place map filters on top of maps
Modified chart_app for unstable, abstracting chart library.

Conflicts:
	descartes_bi/apps/charts/backends/nvd3.py
Each report  is reading from its rederer_options. Templates modified to allow use of options. Chart template code modified, data repeating between charts bug fixed.

Conflicts:
	descartes_bi/apps/charts/backends/nvd3.py
Changes to how charts render, to fix problems with the legend and bar grouping. Added line chart and pie chart.

Conflicts:
	descartes_bi/apps/charts/backends/nvd3.py
Pass report series metadata to chart backends
Add support for specifying the default value of chart backend options
Fix novus backend process_data method, use literals for the chart options