Improve on biome type

[cpfaff]

Currently we have for biome type the following classes of concepts. This does not make me happy actually as it is not clearly separated classes and there is some redundancy to physiognomy class.

Biome Types:

<xs:enumeration value="Terrestrial"/>
<xs:enumeration value="Aquatic"/>
<xs:enumeration value="Ecotone"/>
<xs:enumeration value="Dryland"/>
<xs:enumeration value="Wetland"/>
<xs:enumeration value="Fresh Water"/>
<xs:enumeration value="Brackish Water"/>
<xs:enumeration value="Saline Water"/>

Physiognomy Classes:

<xs:enumeration value="Forest"/>
<xs:enumeration value="Open Woodland"/>
<xs:enumeration value="Shrubland"/>
<xs:enumeration value="Herbaceous System"/>
<xs:enumeration value="Barren Land"/>
<xs:enumeration value="Lake System"/>
<xs:enumeration value="River System"/>
<xs:enumeration value="Marine System"/>

This needs an improvement. Maybe we remove most of the types except for the terrestrial and aquatic for a general classification. Potentially the Ecotone could be implemented as a kind of boolean field just modifying the other description already given in type. That could be done in the way we thought for control factors which either have been controlled for or just have been observed.

We could have:

<xs:enumeration value="Terrestrial Biome"/>
<xs:enumeration value="Aquatic Biome"/>