Make scenario data available

[CherineJ]

The temperature data for the climate scenario RCP 8.5 is currently only a set of 40 locally saved CSV files. In line with the other input data, these files should also be accessible through, for example, an API. It needs to be discussed how/where to store the scenario data.

[CherineJ]

The data for the other climate scenarios (as well as the data for RCP 8.5) are available through a GitHub repository of Matthew Long.
For now, this might be sufficient, if the repository is stable enough to query the data from there. On the long run, another solution needs to be found to store the scenario data.