wiki: Improve consistency of absolute/relative links. - Make links from endpoint pages go to the same endpoint by default. - Add support for `:` (empty) endpoint to link outside of endpoints. - Add unit tests.

sudo: false
language: python
python:
  - "3.4"
  - "3.5"
  - "3.6"
install:
  - "pip install -r requirements.txt"
  - "pip install -r dev-requirements.txt"
script: py.test