[UIMA-4060] improve int set impls, fix one bug in PositiveIntSet, add test cases

git-svn-id: https://svn.apache.org/repos/asf/uima/uimaj/trunk@1633890 13f79535-47bb-0310-9956-ffa450edef68
This was an accidental commit - pushed the wrong button.  I'll attempt to revert

git-svn-id: https://svn.apache.org/repos/asf/uima/uimaj/trunk@1633891 13f79535-47bb-0310-9956-ffa450edef68
[UIMA-4060] have CasSerializerSupport use PositiveIntSet instead of IntHashSet

git-svn-id: https://svn.apache.org/repos/asf/uima/uimaj/trunk@1633892 13f79535-47bb-0310-9956-ffa450edef68
no Jira - 1 word fix in doc.

git-svn-id: https://svn.apache.org/repos/asf/uima/uimaj/trunk@1633894 13f79535-47bb-0310-9956-ffa450edef68