Proposed changes to the wd24 wip 1 EiClasses.xsd schemas

Propose minor changes to the EiClasses.xsd schemas as follows. Note that these changes are reflected in the wip8_ed_mods.zip file that was uploaded. Also note that some of these changes are relfected in previous JIRA submissions,

• Changed EiEventSignalType.emix:marketContext to be optional

• Added elementFormDefault="qualified" to the schema attributes

• Added currentValue attribute to the EiEventSignalType

<xs:element name="currentValue">
<xs:complexType>
<xs:sequence>
<xs:element ref="eitc:signalInformationBase"/>
</xs:sequence>
</xs:complexType>
</xs:element>

• changed the EventDescriptorType.emix:marketContext to EventDescriptorType.eitc:eiMarketContext and made it mandatory.

• changed EiMarketContext.emix:marketContext to be optional