Clean up, add javadoc to code around DupeTimestampBestStatusFilter class.
add junit to wayback-cdx-server subproject
Add a test for DumpTimestampBestStatusFilter.
(add EasyMock 2.5.1 as dependency)
Add DupeTimestampLastBestStatusFilter for timestamp-collapsing to the last best capture, and tests.
Add collapseToLast flag to CDXServer to activate it.