Extend development instructions (#36)

* Extend development instructions

Instructions for collaborators on source code formatting, building the
documentation, and running tests.

Added blue-style badge to README

Added `Makefile`

* Remove `Makefile`

Author: goerz

CONTRIBUTING.md

@@ -17,6 +17,25 @@ To make a good PR, follow these steps:
 5. Feel free to explicitly tag (with `@`) one of the maintainers to request a review of your PR when it is ready.
 
 
+## Source Code Formatting
+
+This project uses the [Blue code style](https://github.com/JuliaDiff/BlueStyle), enforced via [JuliaFormatter](https://github.com/domluna/JuliaFormatter.jl). For pull requests, adherence to the code style is automatically checked during continuous integration.
+
+To apply the code style locally, you should have `JuliaFormatter` installed in your global Julia environment. Then, in a Julia REPL within the `Bijections` project folder, run `using JuliaFormatter; format(".")`.
+
+
+## Running the Tests
+
+In order to run the tests, start a Julia REPL with `julia --project=.`, then type `] test`. This used `Pkg` to run the test suite in a subprocess. When running the tests repeatedly, it may be faster to avoid the subprocess. To run tests directly, start a Julia REPL in the test environment with `julia --project=test`. Consider using [Revise](https://github.com/timholy/Revise.jl). Instantiate with `] instantiate`, then run the tests with `include("test/runtests.jl")`. On Julia < 1.11, you may need `] dev .` to ensure that the test environment uses the current code.
+
+
+## Building the Documentation
+
+To build the documentation locally, start a Julia REPL in the docs environment with `julia --project=docs`. Instantiate with `] instantiate`, then build the documentation with `include("docs/make.jl")`. On Julia < 1.11, you may need `] dev .` to ensure that the test environment uses the current code.
+
+This will build the documentation in `./docs/build`. The preview it, you must run a web server, either via the [LiveServer](https://github.com/JuliaDocs/LiveServer.jl) package, or (if you have Python installed), via `python3 -m http.server`. See the [Documenter Guide](https://documenter.juliadocs.org/stable/man/guide/#Note-6b659cc6046c5199) for details.
+
+
 ## Maintainer Notes
 
 ### Maintainers