XTCE12 — The ToString element used in Integer and Float types overlaps with Enumerated types

Inside of the ToString element, there are possibilities for making number to string mappings that confuse with the Enumerated Parameter/Argument types. These should be removed and the ToString element simplified to satisfy a tighter purpose.

Propose to simplify the ToString element

This is not backwards compatible with any existing documents that use ToStringType, but simplifies the definition of an appropriate format for a numeric parameter and eliminates the confusion with the EnumeratedDataType that many XTCE users experienced. This proposal also eliminates the NumberToStringType which is only used as the base for ToStringType, when ToStringType added no new elements or attributes. This proposal removes the enumeration labels and unnecessary extra elements in the ToString element. Implementation of this proposal also caused validation errors in the schema, due to a typo in a previous resolution. The change to correct that typo is included here, so that the schema will properly validate.

Delete the complexType NumberToStringType

Replace the definition for ToStringType with the following complexType definition:
<complexType name="ToStringType">
<sequence>
<element name="NumberFormat" type="xtce:NumberFormatType" minOccurs="1" maxOccurs="1">
<annotation>
<documentation xml:lang="en">This element describes how a numeric value should be represented in engineering/calibrated form. The defaults reflect the most common form.</documentation>
</annotation>
</element>
</sequence>
</complexType>

Change the case of the 'D' in "decimal" to "Decimal" for the default value for attribute numberBase in complexType NumberFormatType
<attribute name="numberBase" type="xtce:RadixType" use="optional" default="Decimal">