API: use of pipenv instead of pip + virtualenv

fittrackee_api/Dockerfile

@@ -10,7 +10,8 @@ WORKDIR /usr/src/app
 COPY ./requirements.txt /usr/src/app/fittrackee_api/requirements.txt
 
 # install requirements
-RUN pip install -r fittrackee_api/requirements.txt
+RUN pip install pipenv
+RUN pipenv install --system --deploy --ignore-pipfile
 
 # add app
 COPY . /usr/src/app

fittrackee_api/requirements.txt

@@ -1,56 +0,0 @@
-alembic==0.9.9
-apipkg==1.4
-atomicwrites==1.1.5
-attrs==18.1.0
-bcrypt==3.1.4
-certifi==2018.4.16
-cffi==1.11.5
-chardet==3.0.4
-click==6.7
-codacy-coverage==1.3.11
-cookies==2.2.1
-coverage==4.5.1
-execnet==1.5.0
-flake8==3.5.0
-flake8-isort==2.5
-flake8-polyfill==1.0.2
-Flask==1.0.2
-Flask-Bcrypt==0.7.1
-Flask-Migrate==2.1.1
-Flask-SQLAlchemy==2.3.2
-gpxpy==1.2.0
-idna==2.6
-isort==4.3.4
-itsdangerous==0.24
-Jinja2==2.10
-Mako==1.0.7
-MarkupSafe==1.0
-mccabe==0.6.1
-more-itertools==4.2.0
-mysqlclient==1.3.12
-Pillow==5.1.0
-pluggy==0.6.0
-psycopg2-binary==2.7.4
-py==1.5.3
-pycodestyle==2.3.1
-pycparser==2.18
-pyflakes==1.6.0
-PyJWT==1.6.4
-pytest==3.6.1
-pytest-cache==1.0
-pytest-cov==2.5.1
-pytest-flake8==1.0.1
-pytest-isort==0.2.0
-pytest-runner==4.2
-python-dateutil==2.7.3
-python-editor==1.0.3
-python-forecastio==1.4.0
-pytz==2018.4
-requests==2.18.4
-responses==0.9.0
-six==1.11.0
-SQLAlchemy==1.2.8
-staticmap==0.5.3
-testfixtures==6.1.0
-urllib3==1.22
-Werkzeug==0.14.1