crossing: Add readme for crossing presets and fields

Author: tordans

data/presets/highway/crossing/README.md

@@ -1,22 +1,25 @@
 # About the crossing presets
 
+## General
+
+These presets use fields `@templates` to make sure all have a similar structure.
+Some presets like `traffic_signals` have additinal fields and use a different field order.
+Try to keep the file structure very similar so they can be easily compared.
+
 ## nodes `highway=crossing + crossing=*`
 
-This folder `/highway/crossing/*.json` handels the crossing nodes (as geometry type `vertex`).
+Crossing nodes are handel by `highway/crossing.json` + `highway/crossing/*.json` (as geometry type `vertex`).
 
 Crossing nodes and crossing ways have a big overlap.
 However, there are a few tags that should _only_ be expected on the crossing node. When crossing ways are present, this also means there are separate ways attached with additional nodes that hald the
 
-There are places in OSM (of course…) that follow a different tagging style where only crossing ways are used (without the vertex nodes). Those regions might have other conventions on where to place
+There are places in OSM that follow a different tagging style where only crossing ways are used (without the vertex nodes). Those regions might have other conventions on where to place
 
 ## ways `highway=footway|cycleway|path + *=crossing + crossing=*`
 
-Crossing way presets are duplicated per highway class.
-- `/highway/footway/crossing*`
-- `/highway/cycleway/crossing*`
-- `/highway/path/crossing*`
-
-They use fields `@templates` to make sure all have a similar structure.
-Some presets like `traffic_signals` have additinal fields and use a different field order.
+Crossing way presets are duplicated per highway class:
+- `/highway/footway/crossing.json`  + `/highway/footway/crossing/*.json`
+- `/highway/cycleway/crossing.json` + `/highway/cycleway/crossing/*.json`
+- `/highway/path/crossing.json`     + `/highway/path/crossing/*.json`
 
-The crossing presets for `/cycleway/crossing` and `/path/crossing` are considered to be relevant for bike traffic and have additional fields that target bike vs. foot traffic.
+The crossing presets for `/cycleway*` and `/path*` are considered to be relevant for bike traffic and have additional fields that target bike vs. foot traffic.