Parsing an array that was serialized using multipleReferencesAllowed=true fails

[reckart]

Describe the bug
Parsing an array that was serialized using multipleReferencesAllowed=true fails with.

To Reproduce
Try loading these:

<?xml version="1.0" encoding="UTF-8"?>
<typeSystemDescription xmlns="http://uima.apache.org/resourceSpecifier">
    <types>
        <typeDescription>
            <name>test.type</name>
            <description/>
            <supertypeName>uima.tcas.Annotation</supertypeName>
            <features>
                <featureDescription>
                    <name>target</name>
                    <description/>
                    <rangeTypeName>uima.cas.StringArray</rangeTypeName>
                    <elementType>uima.cas.String</elementType>
                    <multipleReferencesAllowed>true</multipleReferencesAllowed>
                </featureDescription>
            </features>
        </typeDescription>
    </types>
</typeSystemDescription>

<?xml version="1.0" ?>
<xmi:XMI xmi:version="2.0" xmlns:cas="http:///uima/cas.ecore"
		 xmlns:tcas="http:///uima/tcas.ecore"
		 xmlns:xmi="http://www.omg.org/XMI"
		 xmlns:test="http:///test.ecore">

	<cas:NULL xmi:id="0"/>

    <tcas:DocumentAnnotation xmi:id="1" sofa="1" begin="0" end="47" language="x-unspecified"/>

    <test:type xmi:id="2" sofa="1" target="3"/>

	<cas:StringArray xmi:id="3">
		<elements>LNC</elements>
		<elements>MTH</elements>
		<elements>SNOMEDCT_US</elements>
	</cas:StringArray>

	<cas:Sofa xmi:id="1" sofaNum="1" sofaID="_InitialView" mimeType="text/plain"
              sofaString="Joe waited for the train . The train was late ."/>
	<cas:View members="1 2" sofa="1"/>
</xmi:XMI>

Expected behavior
Should just work.

Please complete the following information:

• Version: 0.6.0-SNAPSHOT