Use LongestSequencePieceSelector for HTTP/FTP/BitTorrent
integrated downloads. This PieceSelector subclass finds the
longest continuous sequence in the available missing pieces and
selects the last index of such sequence. This makes HTTP/FTP
connections less interrupted by the pieces obtained by
BitTorrent peers.
* src/DefaultPieceStorage.cc
* src/DefaultPieceStorage.h
* src/LongestSequencePieceSelector.cc
* src/LongestSequencePieceSelector.h
* src/Makefile.am
* src/PieceSelector.h
* src/RarestPieceSelector.h
* src/RequestGroup.cc
* test/BtDependencyTest.cc
* test/DefaultPieceStorageTest.cc
* test/IteratableChecksumValidatorTest.cc
* test/LongestSequencePieceSelectorTest.cc
* test/Makefile.am
* test/SegmentManTest.cc