keithbostic noticed that an internal file that does #include <3rdparty/...> causes the python/java builds to fail. This is because the java Makefile and python setup.py }}did not have {{-Isrc/include on the build line. This commit this fixes that.

It probably worked up to now because the SWIG modules use #include "src/include/wt_internal.h" and the top level directory is on the build line and other include files are found directly on that directory. Blame the complexity of gcc/clang include rules for why including a file in a subdirectory behaves differently.