Adding LbAmpGen models in Sim09 to Sim10

Issue to remind us to add the following models from Sim09 to the new and cleaned up Sim10 version of LbAmpGen:

• BtoKpipipi_gamma_*
• LctopKK_v1.opt
• Lctoppipi_v1.opt
• LctoXiKpi_v1.opt
• XictoXiKpi_v1.opt
• XictoXipipi_v1.opt

n.b. these models are all preliminary and at some point in the future should be replaced by final versions.