Restructure code, tox, and Makefile (#466)

* Fix compatibility with Django 3.0 and master
* Add Django 3.0 to tox.ini
* Update versions in requirements.txt
* Use Makefile for common tasks
* Drop MANIFEST.in, use setuptools_scm
* Drop _version.py, use version from git tag

.gitignore

@@ -18,6 +18,7 @@ develop-eggs
 lib
 lib64
 .pip-wheel-metadata
+.eggs
 
 # Installer logs
 pip-log.txt

.travis.yml

@@ -1,13 +1,19 @@
-dist: xenial
-sudo: false
+dist: bionic
 language: python
+
 addons:
-  postgresql: "9.6"
+  postgresql: "9.4"
   apt:
     packages:
-     - postgresql-9.6-postgis-2.3
+      - postgresql-9.4-postgis-2.4
+services:
+  - postgresql
+
 python:
+  - "3.5"
   - "3.6"
   - "3.7"
+  - "3.8"
+
 install: pip install tox-travis
-script: tox
+script: tox

HISTORY.rst

@@ -3,8 +3,8 @@
 History
 -------
 
-12.0.0 (in development)
-+++++++++++++++++++++++
+12.0.0 (2019-12-04)
++++++++++++++++++++
 
 * Drop support for Python 2.7, Django 1.11 and Django 2.0 (#456)
 * Fix Deprecationwarning in Python 3.7 (#455)
@@ -14,6 +14,8 @@ History
 * Add Django 3.0 to `tox.ini`
 * Update versions in `requirements.txt`
 * Use Makefile for common tasks
+* Drop `MANIFEST.in`, use `setuptools_scm`
+* Drop `_version.py`, use version from git tag
 
 11.1.0 (2019-08-09)
 +++++++++++++++++++

Makefile

@@ -1,26 +1,28 @@
-.PHONY: clean test tox reformat lint publish docs build publish
+.PHONY: clean test tox reformat lint docs build publish
 
 clean:
 	rm -rf build dist *.egg-info
 
 test:
-	coverage run manage.py test && coverage report
+	coverage run manage.py test
+	coverage report
 
 tox:
 	rm -rf .tox
 	tox
 
 reformat:
-	isort -rc bootstrap3
-	isort -rc demo
+	isort -rc src/bootstrap3
+	isort -rc example
+	isort -rc tests
 	isort -rc *.py
-	autoflake -ir *.py bootstrap3 demo --remove-all-unused-imports
-	docformatter -ir --pre-summary-newline --wrap-summaries=0 --wrap-descriptions=0 *.py bootstrap3 demo
+	autoflake -ir *.py src/bootstrap3 example tests --remove-all-unused-imports
+	docformatter -ir --pre-summary-newline --wrap-summaries=0 --wrap-descriptions=0 src/bootstrap3 example tests *.py
 	black .
 
 lint:
-	flake8
-	pydocstyle --add-ignore=D1,D202,D301,D413 *.py bootstrap3/ demo/
+	flake8 bootstrap3 src example tests *.py
+	pydocstyle --add-ignore=D1,D202,D301,D413 src example tests *.py
 
 docs:
 	cd docs && sphinx-build -b html -d _build/doctrees . _build/html