Py-ms

**Fixes**
* Fix init services in tests 114
If you import config() `from pyms.flask.app import config` and initialize the config file inside a function like
python
pytest.fixture
def app():
"""
Return app for testing
"""
base_dir = os.path.dirname(os.path.abspath(__file__))
os.environ[CONFIGMAP_FILE_ENVIRONMENT] = os.path.join(base_dir, "config-test.yml")

The singleton pattern not reinitializes the services correctly

**Features**

* Reverse proxy pattern 103
* Added AWS kms support 105
* Added patch method to request service 104 - LiangJQ

**Fixes**

* Don't enable services implicitly 106
When receiving a request, it will return the next error:
text
Tracer error: 'NoneType' object has no attribute 'tracer'

**Fixes**
- Dependency error when not install py-ms with `[all]`. Raise this error:


Traceback:
[...]
from pyms.flask.app import config
../../.local/share/virtualenvs/lib/python3.7/site-packages/pyms/flask/app/__init__.py:1: in <module>
from .create_app import Microservice
../../.local/share/virtualenvs/lib/python3.7/site-packages/pyms/flask/app/create_app.py:6: in <module>
from flask_opentracing import FlaskTracing
ModuleNotFoundError: No module named 'flask_opentracing'

**Fixes**
- [Connexion](https://github.com/zalando/connexion) path in OpenAPI 3.0
In some case, with the last version of Connexion, doesn`t understand relative path to swagger. For example, f you use OpenAPI 3 in your swagger yaml file:


---

**Features**
- Metrics fixes - alexppg
* Add http status code to latency metrics
* Also, change some metrics and labels name to make them more standard.
- Removed required param `path` in Microservice Class. Autodetect the current directory, If you want to deploy the microservice to production with gunicorn we **recommended** use `path`

**Fixes**
- [Connexion](https://github.com/zalando/connexion) path
In some case, with the last version of Connexion, doesn`t understand relative path to swagger

**Features**
Installing pyms with all dependencies

pip install pyms[all]

* Installing minimun dependencies

pip install pyms

* Installing request dependencies

pip install pyms[request]

* Installing swagger dependencies

pip install pyms[swagger]

* Installing metrics dependencies

pip install pyms[metrics]

* Installing trace dependencies

pip install pyms[trace]

* Installing cryptography dependencies

pip install pyms[cryptography]