Some note for developers:

to prepare a virtualenv for dev purposes:
```
pipenv install -e .[test,doc]
```
to generate the sdist distpiecash-XXX.tar.gz:
```
python setup.py sdist
```
to upload file on PyPI:
```
python setup.py sdist upload
```
to generate the modules modules.rst and piecash.rst in the docssourcedoc folder, go to the docssourcedoc folder and:
```
sphinx-apidoc -o . ../../piecash
```
to build the doc (do not forget to pipenv install -e .[doc] before):
```
cd docs
make html
```
The documentation will be available through docs/build/html/index.html.
to test via tox and conda, create first the different environment with the relevant versions of python:
```
conda create -n py35 python=3.5 virtualenv
conda create -n py36 python=3.6 virtualenv
...
```
adapt tox.ini to point to the proper conda envs and then run:
```
tox
```
to release a new version:
1. update metadata.py
2. update changelog
3. tag MM.mm.pp
4. python setup.py sdist upload
to release a new version with gitflow:
1. git flow release start 0.18.0
2. update metadata.py
3. update changelog
4. git flow release finish
5. checkout master branch in git
6. python setup.py sdist upload

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