Fix dictionary check action and standardise the make command we run (#1647)

* Update .travis.yml

* Add more debugging to make

* Removing some extra make debug

* Warn if the dictionary tests won't be run

* Remove the make verbosity again

* Install the required dependencies

* Try and install via the right version of pip

* Add a dev extras section

* Switch to the dev extras to install the codespell dev packages

* Install the codespell dev packages via pip

* We need to checkout to have our file

* Install general dependencies

* Add more stuff to extras

* Install the extras from the right directory

Also move more stuff to extras

* Remove the packages installed via the dev packaging and standardise the order with Travis

* Fix the flake8 warnings

* Make the missing test dependencies a fatal error

* Add a note about dev to the readme

* Update README.rst formatting

Co-authored-by: Eric Larson <larson.eric.d@gmail.com>

* Tweak licence detail formatting

Co-authored-by: Eric Larson <larson.eric.d@gmail.com>

* Pull coverage in as a dependency

* Pull coverage in as a dependency

* Add flake8 to our dev and sort the requirements

* Add a check action which calls flake8, check-manifest and check-dictionaries

* Add the other bits of checking to Makefile

* Switch to make check

* Try running make check on appveyor

* Add a note about make check

* No make on appveyor

Co-authored-by: Eric Larson <larson.eric.d@gmail.com>