translation updates
hardcode language fallback for Norwegian Bokmå
show language names in lng selector dropdown
drop welcome message
update/improve help

* drop welcome message dialog (and put short general introduction
  into the help dialog instead)
* reworked general introduction (less technical stuff)
* document query wizard keyboard shortcut
* own help section about query shortcuts
* document more query shortcuts (date, style)
prevent overflowing error dialogs

see #77
prevent popups from getting too large, overflowing the screen

this happens quite often on POIs with many tags, e.g. countries
or cities with names translated in to many languages.
try harder to parse failing wizard searches

if normal parsing fails, try to parse it ffs-only "<search>".
more diverse query wizard examples

closes #81
More detailed help text in wizard dialog with direct link to documentation.

fixes #91