docs: fix and improve CONTRIBUTING.rst

Author: samineer

CONTRIBUTING.rst

@@ -4,22 +4,25 @@ Contributing to fluent-compiler
 Issues
 ------
 
-You can help by filing bugs on GitHub: https://github.com/django-ftl/fluent-compiler/issues
+You can help by filing bugs on GitHub:
+https://github.com/django-ftl/fluent-compiler/issues.
 
 Please check existing issues before filing a new one.
 
+
 Development environment
 -----------------------
 
-To contribute fixes and features, you'll need to get set up for development:
+To contribute fixes and features, you'll need to get set up for
+development:
 
-1. For ``fluent_compiler`` on github
-2. Checkout a copy of the project using
-3. Create a virtualenv for development (or your preferred mechanism
-   for isolated Python environments)
+1. Fork ``fluent_compiler`` on GitHub.
+2. Clone and go to the forked repository.
+3. Create and activate a virtual environment for development (or your
+   preferred mechanism for isolated Python environments).
 4. Install the package in development mode::
 
-     ./setup.py develop
+     pip install -e .
 
 5. Install test requirements::
 
@@ -34,27 +37,28 @@ If all that is successful, you are in good shape to start developing!
 We also have several linters and code formatters that we require use of,
 including `flake8 <http://flake8.pycqa.org/en/latest/>`_, `isort
 <https://github.com/timothycrosley/isort#readme>`_ and `black
-<https://github.com/psf/black>`_. These are most easily add by using `pre-commit
-<https://pre-commit.com/>`_:
+<https://github.com/psf/black>`_. These are most easily add by using
+`pre-commit <https://pre-commit.com/>`_:
 
-* Install pre-commit globally e.g. ``pipx install pre-commit`` if you already
-  have `pipx <https://github.com/pypa/pipx>`_.
+* Install pre-commit globally e.g. ``pipx install pre-commit`` if you
+  already have `pipx <https://github.com/pypa/pipx>`_.
 
 * Do ``pre-commit install`` in the repo.
 
 Now all the linters will run when you commit changes.
 
-To run tests on multiple Python versions locally you can also install and use
-``tox``.
+To run tests on multiple Python versions locally you can also install
+and use ``tox``.
 
 
 Fixes and features
 ------------------
 
 Please submit fixes and features by:
 
-1. First creating a branch for your changes
-2. Sending us a PR on GitHub
+1. First creating a branch for your changes.
+2. Sending us a PR on GitHub.
 
-For new features it is often better to open an issue first to see if we agree
-that the feature is a good idea, before spending a lot of time implementing it.
+For new features it is often better to open an issue first to see if we
+agree that the feature is a good idea, before spending a lot of time
+implementing it.