Add decay files for Lambda_c -> eta (eta') p (Sigma) and D+->eta' pi(K)

A total of ten new decay files are added by this MR. They all requires only that the decay products are in the LHCb acceptance and they will be used for HLT2 lines development.

\Lambda_c^+ \to \eta p, \eta \to \pi^+ \pi^- \pi^0, \pi^0 \to \gamma \gamma

\Lambda_c^+ \to \eta p, \eta \to \pi^+ \pi^- \gamma,

\Lambda_c^+ \to \eta' p, \eta' \to \rho^0 \gamma, \rho^0 \to \pi^+ \pi^-

\Lambda_c^+ \to \eta' p, \eta' \to \pi^+ \pi^- \eta, \eta \to \gamma \gamma

\Lambda_c^+ \to \eta \Sigma^+, \Sigma^+ \to p \pi^0, \pi^0 \to \gamma \gamma, \eta \to \pi^+ \pi^- \pi^0, \pi^0 \to \gamma \gamma

\Lambda_c^+ \to \eta \Sigma^+, \Sigma^+ \to p \pi^0, \pi^0 \to \gamma \gamma, \eta \to \pi^+ \pi^- \gamma,

\Lambda_c^+ \to \eta' \Sigma^+, \Sigma^+ \to p \pi^0, \pi^0 \to \gamma \gamma, \eta' \to \rho^0 \gamma, \rho^0 \to \pi^+ \pi^-

\Lambda_c^+ \to \eta' \Sigma^+, \Sigma^+ \to p \pi^0, \pi^0 \to \gamma \gamma, \eta' \to \pi^+ \pi^- \eta, \eta \to \gamma \gamma

D^+ \to \eta' K^+, \eta' \to \rho^0 \gamma, \rho^0 \to \pi^+ \pi^-

D^+ \to \eta' \pi^+, \eta' \to \rho^0 \gamma, \rho^0 \to \pi^+ \pi^-