Fix pair.morse ULF error on Fermi.
Fix pair.morse ULF error on Fermi.

Root cause appeared to be a float4 shared memory read alignment violation.
Rearranging the parameters stored in shared memory solves the ULF.

git-svn-id: 4ba210d0a933e3fb1aa9ab096f190cd38965d92a@2964 fa922fa7-2fde-0310-acd8-f43f465a7996

joaander/hoomd-blue,joaander/hoomd-blue,joaander/hoomd-blue,joaander/hoomd-blue,joaander/hoomd-blue,joaander/hoomd-blue