Define 'MAP_ANONYMOUS' on Darwin

'MAP_ANONYMOUS' is not part of the POSIX standard, and Darwin defines
it as 'MAP_ANON'. On Darwin, define 'MAP_ANONYMOUS' to be an alias for
'MAP_ANON'.

Signed-off-by: Jussi Virtanen <jussi.k.virtanen@gmail.com>
Define 'MADV_HUGEPAGE' on Darwin

Simply define it as 'MADV_NORMAL' for now.

Note: The use of 'MADV_*' constants (as opposed to 'POSIX_MADV_*'
constants) with 'posix_madvise' is a potential cause for portability
issues later on.

Signed-off-by: Jussi Virtanen <jussi.k.virtanen@gmail.com>
Use 'JAVA_HOME' environment variable

Signed-off-by: Jussi Virtanen <jussi.k.virtanen@gmail.com>