Extend docs, add link to sample implementation, update changelog

Author: nezhar

CHANGELOG.md

@@ -4,7 +4,7 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
-## [Unreleased]
+## [0.4.0]
 
 ### Added
 - `-pr`, `--pre-releases` parameter to explicitly enable display of pre-releases in console
@@ -49,7 +49,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 ### Added
 - Initial Release
 
-[Unreleased]: https://github.com/nezhar/updatable/compare/v0.3.1...HEAD
+[0.4.0]: https://pypi.org/project/updatable/0.4.0/
 [0.3.1]: https://pypi.org/project/updatable/0.3.1/
 [0.3.0]: https://pypi.org/project/updatable/0.3.0/ 
 [0.2.0]: https://pypi.org/project/updatable/0.2.0/

README.rst

@@ -6,7 +6,7 @@ Updatable
 .. image:: https://codecov.io/gh/nezhar/updatable/branch/master/graph/badge.svg
   :target: https://codecov.io/gh/nezhar/updatable
 
-Finds packages that require updates on a python environment
+Updatable help you to find packages that require updates on a python environment.
 
 Installation
 ~~~~~~~~~~~~
@@ -18,6 +18,9 @@ The latest release of updatable can be installed via PyPI:
     pip install -U updatable
 
 
+It can be installed globally or in virtual environment, depending on where you plan to check the dependencies.
+If you have a ``requirements.txt`` with pinned dependencies you can pass it as an argument to check against it.
+
 The project supports Python ``2.7``, ``3.4``, ``3.5``, ``3.6``, ``3.7``, ``3.8`` as well as ``pypy`` and ``pypy3``.
 
 
@@ -27,7 +30,11 @@ Usage
 The package can be used as a command line tool, so you can get a list of all
 packages that require updates from your current environment. You may also use
 the package inside of your python application, to list the packages over a REST
-endpoint, forward them by mail or other purpose.
+endpoint (see a `sample implementation here`__), forward them by mail or other purpose.
+
+.. _Implementation: https://github.com/anexia-it/anexia-monitoring-django
+__ Implementation_
+
 
 Example:
 ::

setup.py

@@ -100,6 +100,7 @@ def run(self):
         'Programming Language :: Python :: 3.5',
         'Programming Language :: Python :: 3.6',
         'Programming Language :: Python :: 3.7',
+        'Programming Language :: Python :: 3.8',
         'Programming Language :: Python :: Implementation :: CPython',
         'Programming Language :: Python :: Implementation :: PyPy',
         'Intended Audience :: Developers',