Bug-22104 - Added jal_memdup function for 3 buffers that are not null terminated (sys meta, app meta, payload) and fixed the jal_strndup function (although no one calls it now).

Bug-22104 - Added test cases for jal_strndup and jal_memdup.

Bug-22104 - Fixed Sconsript to remove duplicate lines. Units tests were running twice for debug and twice for release.

Bug-22104 - Fixup.