Adapt the docker-compose setup for coprocessor to rc35+

[manoranjith]

In the release v0.9.0-rc35 and the following ones for kms images, a change that is not compatible with current setup of docker compose was introduced.

Previously, the gateway need not be aware of the crs_id or key_id. It had a way to query the kms-blockchain for all the existing key's and crs's.

In v0.9.0-rc35 and further release, these two values should be specified by the gateway when querying the kms blockchain. These values are obtained as a result of running the simulator to generate the key and crs. The docker compose setup should be modified in the following way:

1. After the simulator generates the key and crs, it should stored the value of key_id and crs_id in a .env file in a volume shared by: simulator and gateway containers.
2. The gateway container, before running the gateway should source this .env file. The environment variables take priority over values in config files (see this test).

[manoranjith]

cc: @leventdem @RomanBredehoft