When we enter an empty string in nillable number,

Use the value null instance of "".
Merge pull request #86 from sbrunner/null-number

When we enter an empty string in nillable number,
Always remove all the item to keep the legend in the right order.

Also reverse the layer for the same reason.
allowDecimals and allowNegative set for number fields
fixed tests
do not enforce arbitrary decimal precision
WMSCapabilitiesReader generates layer attribution object
Merge pull request #90 from georchestra/attribution

WMSCapabilitiesReader generates layer attribution object
Merge pull request #89 from georchestra/record2field

GeoExt.form.recordToField: setting allowDecimals and allowNegative in number field
Merge pull request #87 from sbrunner/wmslwgend-order

Always remove all the item to keep the legend in the right order.