Add a new vector, concatenated_ratematrix_elements , to the report in TMB

[stevencarlislewalker]

This vector is the concatenation of the non-zero elements of the rate matrix for every time step. This is similar to concatenated_state_vector

[stevencarlislewalker]

closed with https://github.com/mac-theobio/McMasterPandemic/commit/f0c8cb878e48e254c71238b966604d43812beb4d