Update files to use Poetry >=0.12.0

Author: sdispater

.gitignore

@@ -31,7 +31,8 @@ profile.html
 /wheelhouse
 /docs/site/*
 pyproject.lock
+/poetry.lock
 
 # editor
 
-.vscode
+.vscode

.travis.yml

@@ -63,7 +63,9 @@ install:
         virtualenv --python="$PYENV_ROOT/versions/pypy-$PYPY_VERSION/bin/python" "$HOME/virtualenvs/pypy-$PYPY_VERSION"
         source "$HOME/virtualenvs/pypy-$PYPY_VERSION/bin/activate"
       fi
-  - pip install poetry -U
+  - pip install pip -U
+  - curl -sSL https://raw.githubusercontent.com/sdispater/poetry/master/get-poetry.py | python
+  - source $HOME/.poetry/env
   - poetry install -v
   - poetry build -v
   - |

pyproject.toml

@@ -33,3 +33,8 @@ cleo = "^0.6.1"
 tox = "^3.0"
 black = { version = "^18.4-alpha.0", python = "^3.6" }
 pre-commit = "^1.10"
+
+
+[build-system]
+requires = ["poetry>=0.12"]
+build-backend = "poetry.masonry.api"