r.reclass.area: add upper and lower option and rewrite with Tools API

scripts/r.reclass.area/r.reclass.area.md

@@ -1,10 +1,25 @@
 ## DESCRIPTION
 
-*r.reclass.area* reclasses a raster map greater or less than a user
-specified area size (in hectares).
+*r.reclass.area* removes areas (pixel clumps) from a raster map
+that are smaller than a user specified **lower** area size and/or
+greater than a user specified **upper** theshold (both in hectares).
 
-If the **-c** flag is used, *r.reclass.area* will skip the creation of a
-clumped raster and assume that the input raster is already clumped.
+*r.reclass.area* provides two **method**s for filtering:
+
+- *reclass* - raster based filtering
+- *rmarea* - vector based filtering
+
+With the *reclass* method, the input raster map is clumped and
+then reclassified using the clump size. With the **-m** flag,
+*reclass* method will remove small areas already during clumping,
+using the *minsize* option there. If the **-c** flag is used,
+*r.reclass.area* will skip the creation of a clumped raster and
+assume that the input raster map is already clumped.
+
+The *rmarea* method converts the raster map to vector and removes
+areas outside the given thresholds using [v.clean](v.clean.md) and
+[v.edit](v.edit.md). With the **-v** flag the **output** is the
+filtered vector map instead of a raster.
 
 ## EXAMPLES
 
@@ -19,7 +34,7 @@ r.report zipcodes unit=h
 Extract only areas greater than 2000 ha, NULL otherwise:
 
 ```sh
-r.reclass.area input=zipcodes output=zipcodes_larger2000ha mode=greater value=2000
+r.reclass.area input=zipcodes output=zipcodes_larger2000ha greater=2000
 
 r.report zipcodes_larger2000ha unit=h
 ```
@@ -30,21 +45,23 @@ r.report zipcodes_larger2000ha unit=h
 In this example, the ZIP code map in the North Carolina sample dataset
 is filtered for smaller areas which are substituted with the value of
 the respective adjacent area with largest shared boundary. Reclass by
-substitutional removing of areas minor of 1000 ha:
+substitutional removing of areas smaller than 1000 ha:
 
 ```sh
-r.reclass.area input=zipcodes output=zipcodes_minor1000ha mode=lesser value=1000 method=rmarea
+r.reclass.area input=zipcodes output=zipcodes_minor1000ha lesser=1000 method=rmarea
 ```
 
 ![Figure: r.reclass.area method=rmarea](zipcodes_minor1000ha.png)  
 *Figure: r.reclass.area method=rmarea*
 
 ## SEE ALSO
 
-*[r.reclass](r.reclass.md), [r.clump](r.clump.md),
-[r.stats](r.stats.md)*
+*[r.clump](r.clump.md), [r.reclass](r.reclass.md),
+[r.stats](r.stats.md), [v.to.rast](v.to.rast.md),
+[v.clean](v.clean.md), [v.edit](v.edit.md)*
 
 ## AUTHORS
 
 NRCS,  
 Markus Neteler
+Stefan Blumentath