MacZFS 78-1, synchronized with onnv_78

With special thanks to Björn Kahl, who went above and beyond the call
of duty to make this happen

Updated installer script to suport 10.8 Mountain Lion.

MacZFS-78 is synchronized with OpenSolaris onnv_78

Preview support for Lion

Testing by others indicates that the current binary works on
OSX 10.7 (Lion) preview systems. Update the installer to allow
installing on Lion systems.

Issue: http://code.google.com/p/maczfs/issues/detail?id=86

MacZFS-77 is synchronized with OpenSolaris onnv_77

MacZFS-76 is synchronized with OpenSolaris onnv_76

Merge commit 'onnv_73' into pre_merge_73

MacZFS-75 is synchronized with OpenSolaris onnv_75

MacZFS-75 is synchronized with OpenSolaris onnv_75

MacZFS-74, synchronized to OpenSolaris onnv_74