Add functionality of time-dependent costs for FixCosts, specificCosts, and divestCosts

[FBumann]

[FBumann]

Investments get transformed to a TS with the costs equally distributed over time.
Longer Time steps get a bigger amount assigned.
costs[i] = dt[i] / t_total * costs_total

[FBumann]

effects results:
shares
sum_TS
sum
Should work automatically

[FBumann]

This should make "exists" redundant, or does it?

[FBumann]

Closed for now due to rework #53