move check for multiline string into SQL

Should speed up things a bit for 404 results as the 'uninteresting' geometries
never leave postgres.
Also moved the DB query after the cache check assuming that access
to the cache is normally faster.
add copyright header
add authors file
hide elevation section if no data is available
add attribution to pistes-nordiques and ASTER
Localisation updates from http://translatewiki.net.
switch to self-hosted hillshading layer

The new layer is intense enough that the layer duplication can be
dropped.
drop unused jquery in docpage
Localisation updates from http://translatewiki.net.
Added elevationheight to the HTML output
Changed to accumulated ascent/descent
Tried to make some sensible calculations for ascent, descent
Merge branch 'elevationheight' of https://github.com/esisa/waymarked-trails-site into elevationheight

Conflicts:
	django/src/routemap/apps/routeinfo/elevationprofile.py
	static/js/ElevationProfile.js