Build and test backend without docker

Build and test the backend without docker so that tests can be run
against pull requests from forks. Fixes #17

.travis.yml

@@ -1,20 +1,3 @@
-image: docker:latest
-language: python
-
-env:
-  global:
-    - DOCKER_DRIVER=overlay2
-    - DOCKER_HOST=tcp://localhost:2375
-
-    - BASE_IMAGE_REGISTRY=gcr.io/mycrocoin
-    - BACKEND_IMAGE=${BASE_IMAGE_REGISTRY}/mycro-backend
-    - FRONTEND_IMAGE=${BASE_IMAGE_REGISTRY}/mycro-frontend
-    - TEST_IMAGE=${BASE_IMAGE_REGISTRY}/test
-
-stages:
-  - test
-
-
 jobs:
   include:
     - stage: unit test
@@ -30,21 +13,27 @@ jobs:
       script:
         - npm run prettier-check
     - stage: unit test
+      language: python
+      python:
+        - "3.6"
+      dist: xenial
       services:
-        - docker
         - postgresql
       addons:
         postgresql: "9.6"
+      before_install:
+#        - echo $PATH
+#        - return 1
+#        - sudo add-apt-repository -y ppa:ethereum/ethereum
+#        - sudo apt-get update -y
+        - sudo apt-get install -yq --no-install-recommends --no-install-suggests automake build-essential libffi-dev libgmp-dev libssl-dev libtool pkg-config python3-dev python3-pip software-properties-common
+      install:
+        - cd backend
+        - pip3 install -r requirements.txt
+        - python3 -m solc.install v0.4.24
+        - ln -s /home/travis/.py-solc/solc-v0.4.24/bin/solc /usr/bin/solc
       before_script:
-        - docker login -u _json_key -p "$(echo $GCR_REGSITRY_SERVICE_ACCOUNT | base64 -d)" https://gcr.io
         - psql -c 'create database travis_ci_test;' -U postgres
       script:
-        # need to support branches with / in the their name. Do this by replacing / with -
-        - IMAGE_WITH_TAG=$TEST_IMAGE:${TRAVIS_PULL_REQUEST_BRANCH:-$TRAVIS_BRANCH}
-
-        - docker pull $IMAGE_WITH_TAG || docker pull $TEST_IMAGE:latest || true
-        - docker build --cache-from $IMAGE_WITH_TAG --cache-from $TEST_IMAGE:latest -t $IMAGE_WITH_TAG -t $TEST_IMAGE:latest -f server.Dockerfile .
-        - docker push $IMAGE_WITH_TAG # push this first so we don't have to rebuild if tests fail
-        - docker run --net=host $IMAGE_WITH_TAG python manage.py test -v 2
-        - docker push $TEST_IMAGE:latest
-
+        - cd ..
+        - python manage.py test -v 2