-Add the following modes to synth:
-MODE_SHIFTNSTRETCH 14
-MODE_SHIFTTANGENT 15
-MODE_XMIRROR 17
-MODE_XYMIRROR 18
-MODE_SPHERICAL2 19
-Clamp synth_mode, synth_*_type and synth_*_layer to valid values.
--Bug fixes
-synth was broken due to passing synth_mode to Interpolate, rather than synth_smooth.
-Fix bad include and link path in EmberAnimate project.