[Imports] import guidelines, new rules proposal

[Jason Remillard]

Hi,

Many of the import/robot guidelines, could be simplified, if we
adopted a new/more general rule.

A "good" import results in OSM data that is indistinguishable from
normally mapped data.

Generally, normal mappers would not

 - put down a node every half meter on a straight line.
 - map a feature twice, or otherwise ignore data that is already in the map.
 - create a new node for a POI, when the building is already in OSM.
 - use non-standard tags with no documentation in our wiki. It should
not go into the database via an import if we don't have an
standardized way of tagging it by now.
 - type in an address in all caps.
 - map a feature 100 meter from its true position, when high quality
satellite images are available.
 - create a change sets with 50,000 elements.
 - create a map with a complex network of relations, when a simpler
data representation is possible
 - etc...

Insisting that imported data be indistinguishable from normally mapped
data might make it easier to communicate with people wishing to do
imports by providing an overriding framework/justification for our
many existing guidelines.

Thanks
Jason.