Revision 552385

SOLR-133 -- found a bug in the delete XML parsing.  for id's and queries with &, it did not behave correctly.  Adds a fix and test.  Another sideeffect that should be noted is that this parser now accepts multiple delete commands:

<delete>
 <id>1</id>
 <id>3</id>
 <id>4</id>
</delete`>