add lucene-copydatabase

	modified:   xapian-core/api/lucenefieldproc.cc
	modified:   xapian-core/api/omdatabase.cc
	modified:   xapian-core/api/omdocument.cc
	modified:   xapian-core/api/omenquire.cc
	modified:   xapian-core/api/postingiterator.cc
	modified:   xapian-core/api/query.cc
	modified:   xapian-core/api/queryinternal.cc
	modified:   xapian-core/api/queryinternal.h
	modified:   xapian-core/api/termiterator.cc
	modified:   xapian-core/api/termlist.cc
	modified:   xapian-core/api/termlist.h
	modified:   xapian-core/backends/chert/chert_database.cc
	modified:   xapian-core/backends/database.cc
	modified:   xapian-core/backends/database.h
	modified:   xapian-core/backends/lucene/Makefile.mk
	modified:   xapian-core/backends/lucene/bytestream.cc
	modified:   xapian-core/backends/lucene/lucene_database.cc
	modified:   xapian-core/backends/lucene/lucene_database.h
	modified:   xapian-core/backends/lucene/lucene_document.cc
	modified:   xapian-core/backends/lucene/lucene_document.h
	modified:   xapian-core/backends/lucene/lucene_fdtxtable.cc
	modified:   xapian-core/backends/lucene/lucene_fdtxtable.h
	modified:   xapian-core/backends/lucene/lucene_fnmtable.cc
	modified:   xapian-core/backends/lucene/lucene_frqtable.cc
	modified:   xapian-core/backends/lucene/lucene_frqtable.h
	modified:   xapian-core/backends/lucene/lucene_nrmtable.cc
	modified:   xapian-core/backends/lucene/lucene_segdb.cc
	modified:   xapian-core/backends/lucene/lucene_segdb.h
	modified:   xapian-core/backends/lucene/lucene_segmentgentable.cc
	modified:   xapian-core/backends/lucene/lucene_segmenttable.cc
	modified:   xapian-core/backends/lucene/lucene_term.cc
	modified:   xapian-core/backends/lucene/lucene_term.h
	modified:   xapian-core/backends/lucene/lucene_termindex.cc
	modified:   xapian-core/backends/lucene/lucene_termindex.h
	modified:   xapian-core/backends/lucene/lucene_tiitable.cc
	modified:   xapian-core/backends/lucene/lucene_tistable.cc
	modified:   xapian-core/backends/lucene/lucene_tistable.h
	modified:   xapian-core/examples/Makefile.mk
	modified:   xapian-core/include/xapian/database.h
	modified:   xapian-core/include/xapian/postingiterator.h
	modified:   xapian-core/include/xapian/termiterator.h
	modified:   xapian-core/weight/bm25weight.cc
	modified:   xapian-core/weight/weight.cc