Update .travis files

 - move triggers (BB/Win/OSX) to before_script section
 - update DROPBOX_KEY for windows
 - copy archive binaries to dropbox
 - do not use custom lcov. just use ctest -ExperimentalCoverage
Use "--gen-suppressions=all" in valgrind
Update memcheck.supp to match the thread bug patterns we get by using clang++-3.3