Extend contribution type information within docs

[FabiKo117]

Out of a recent discussion with @Zia- we found out that the descriptions regarding the contribution type within our docs are a bit insufficient. Here is an example explanation about valuable info that is partially missing:

a) if a new feature gets created OR moved into your requested area of interest OR is now fitting to your defined filter parameter it should have the "@creation":"true" parameter
b) if a feature gets deleted OR moved outside of your requested area of interest OR is not fitting anymore to your defined filter parameter it should have the "@deletion":"true" parameter
c) if the geometry of a feature is modified, it gets the "@geometryChange":"true" parameter

[FabiKo117]

Additional info regarding geometry changes:

a geometryChange for on osm-way can happen when

• a certain tag changed (e.g. highway=yes to building=yes)
• the order or member get deleted/added
• a member (node) moved/deleted

for an osm-relation geometry change can happen when

• a certain tag changed
• the order of the members (also del/add)
• a member geometry changed, see osme-way geometry change

[tyrasd]

I could imagine that the additional info regarding geometry changes could be confusing if a user isn't super proficient about the OSM data modes. Also, for example, the order of members is not actually what determines if a contribution is a geometry change or not. When, for example an outer way member of a multipolygon relation is split into two parts, but otherwise left unchanged including its node coordinates, there would be a change of the member list of the multipolygon relation (i.e. an addition of a new outer way and a member geometry changed), but (the OSHDB and) the ohsome API would not report this as a contribution with "@geometryChange" : true, since the geometry of the resulting (multi)polygon feature stayed the same during this operation.

c) if the geometry of a feature is modified, it gets the "@geometryChange":"true" parameter

IMHO, think this definition is short, comprehensive and sufficient.