Bitbetter identity Core.dll (#14)

* Added a Key Generating script

To make the keygen process a bit easier I've added a `generate-keys.sh` script that can be found in the `.keys` directory. It will generate the key & cert and bundle them into the required pkcs#12 file automatically when running the build script if none already exist.

* Generate bitbetter/identiry container with modified Core.dll

Added the generation of a second modified container, bitbetter/identity, which contains the modified dll. Fixes #12.

This works on my testing environment but has not gone through extensive testing. I'd recommend a review and cleanup of this commit before it is merged into the develop or master branches.

.circleci/config.yml

@@ -10,6 +10,9 @@ jobs:
           command: date
       - setup_remote_docker
       - run: { name: 'Get docker', command: 'curl -fsSL get.docker.com -o get-docker.sh && sh get-docker.sh' }
+      - run:
+          name: Generate Keys
+          command: ./.keys/generate-keys.sh
       - run:
           name: Build script
           command: ./build.sh