JBIDE-8428 Content assist inside #{} in text element of xhtml shows JSF ...

...tags as proposals

The issue is fixed. All the Non-EL proposals are filtered out from the proposal list when the Content Assist
is invoked from the position inside EL (#{...}).
JUnit Test org.jboss.tools.jsf.jsp.ca.test.CAELNoTagProposalsInELTest

	deleted:    common/plugins/org.jboss.tools.common.text.xml/schema/contentAssistProcessor.exsd
	deleted:    common/plugins/org.jboss.tools.common.text.xml/src/org/jboss/tools/common/text/xml/contentassist/ContentAssistProcessorBuilder.java
	deleted:    common/plugins/org.jboss.tools.common.text.xml/src/org/jboss/tools/common/text/xml/contentassist/ContentAssistProcessorDefinition.java
	modified:   common/plugins/org.jboss.tools.common.text.xml/src/org/jboss/tools/common/text/xml/contentassist/ProposalSorter.java
	deleted:    common/plugins/org.jboss.tools.common.text.xml/src/org/jboss/tools/common/text/xml/contentassist/SortingCompoundContentAssistProcessor.java