updates after Zurich meeting

[matthiasdusch]

• change name to RGI-TOPO
• rephrase some parts to indicate official release together with new RGI
• include new dem_source Notebook Update RGI-TOPO related notebooks OGGM/oggm-edu-notebooks#18
• update existing example graphics with equal colorbars and @fmaussion diff_plot changes
• add even more examples. I want to cover other regions like high mountain Asia, Scandinavia, Arctic Canada, Russia, NZ, ...
• maybe Remove dependency to OGGM #30
• rework the DEM hompage a bit: I'd like to put the table with the statistics for the subregions into separate pages to keep it clearer.

started most of this and will finish in the office

[matthiasdusch]

ok, done everything except the #30 issue. But to go forward (public) I'd say merge this now and implement the download function some other time.

[fmaussion]

Awesome! I'll play around a bit tonight and lets aim to send this out to review to the RGI committee tomorrow