Use different python image

Dockerfile.prod

@@ -1,16 +1,9 @@
-FROM python:alpine
+FROM python:3.5
 ENV PYTHONUNBUFFERED 1
 ENV IS_DOCKER 0
 WORKDIR /app
 COPY requirements.txt ./
 COPY requirements.production.txt ./
-
-RUN apk add --no-cache --virtual .build-deps build-base linux-headers \
-    && apk add --no-cache jpeg-dev zlib-dev postgresql-dev \
-    && pip install -r requirements.txt \
-    && pip install -r requirements.production.txt \
-    && apk del .build-deps
-
 COPY . ./
 COPY sikweb/settings-sample-prod.py settings.py