Merge branch 'jlanger/Bd2DstDst_CP' into 'master'

Bd2DstDst CPV MC + Bs2DstDst polarised MC

See merge request !1685 (merged)

(cherry picked from commit 78def3e8)

4a1bc88f added Bd2DstDst CPV decfiles for several D0 final states c5e931ba added DecFiles for generating polarised Bs MC b1b67f45 changed date for polarised Bs DecFiles 633818b4 added definitions of the parameters, fixes the the decfiles 0e39adc8 moved down definitions