Simplify install instructions

Stack doesn't understand the new build-tool-depends so removed this for now.

README.md

@@ -81,31 +81,11 @@ You can also find generic Linux and Mac OS binaries here:
 
 ### From source
 
-Installation from source is very easy.  You can build from source using `stack
-install` or `cabal install`.  `patat` is also available from [Hackage].
-
-[Hackage]: https://hackage.haskell.org/package/patat
-
-For people unfamiliar with the Haskell ecosystem, this means you can do either
-of the following:
-
-#### Using stack
-
-1. Install [stack] for your platform.
-2. Clone this repository.
-3. Run `stack setup` (if you're running stack for the first time) and
-   `stack install`.
-4. Make sure `$HOME/.local/bin` is in your `$PATH`.
-
-[stack]: https://docs.haskellstack.org/en/stable/README/
-
-#### Using cabal
-
-1. Install [cabal] for your platform.
-2. Run `cabal install patat`.
-3. Make sure `$HOME/.cabal/bin` is in your `$PATH`.
+`patat` is also available from [Hackage].  You can install it using [cabal] by
+running `cabal install patat`.
 
 [cabal]: https://www.haskell.org/cabal/
+[Hackage]: https://hackage.haskell.org/package/patat
 
 Running
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