Disabling 'project finance' feature locks cost model to 'technical + leadership + indirects'

[cjfullerton]

With the Project Finance feature disabled, the project cost model can't be changed and is set to 'technical + leadership + indirects'.

This leads to increased FTE assignments showing in brackets against tasks to cover indirect contribution.

Suggested fixes: remove increased FTE when project finance disabled or set simpler cost model (technical only?)