update doc index

Author: bjornregnell

docs/index.md

@@ -2,7 +2,7 @@
 ---
 
 This is the documentation of the `introprog` Scala Library with beginner-friendly utilities used in computer science teaching at Lund University.
-The code repository is hosted at [[https://github.com/lunduniversity/introprog-scalalib]].
+The open source code is hosted at [[https://github.com/lunduniversity/introprog-scalalib]].
 
 ## Package contents
 
@@ -20,21 +20,29 @@ The code repository is hosted at [[https://github.com/lunduniversity/introprog-s
 
 ## How to use this library with `sbt`
 
-If you have [sbt](https://www.scala-sbt.org/) version 1.5.2 or later installed then you can put this text in a file called `build.sbt`
+If you have [sbt](https://www.scala-sbt.org/) installed then you can put this text in a file called `build.sbt`
 
 ```
 scalaVersion := "3.0.2"
 libraryDependencies += "se.lth.cs" %% "introprog" % "1.3.1"
 ```
 
-You can find the latest version of introprog-scalalib on [scaladex](https://index.scala-lang.org/lunduniversity/introprog-scalalib/introprog).
-
-When you run `sbt` in a terminal the introprog lib is automatically downloaded and made available on your classpath.
-Then you can do things like:
+When you run `sbt` in a terminal, with the above in your `build.sbt`, the introprog lib is automatically downloaded and made available on your classpath. Then you can do things like:
 
 ```
-> sbt
 sbt> console
 scala> val w = new introprog.PixelWindow()
 scala> w.fill(100,100,100,100,java.awt.Color.red)
 ```
+
+## Manual download
+
+You can also manually download the latest jar file from here: 
+
+* Lund University: [http://www.cs.lth.se/pgk/lib](http://www.cs.lth.se/pgk/lib) 
+
+* GitHub: [https://github.com/lunduniversity/introprog-scalalib/releases](https://github.com/lunduniversity/introprog-scalalib/releases)
+
+* ScalaDex: [https://index.scala-lang.org/lunduniversity/introprog-scalalib/introprog](https://index.scala-lang.org/lunduniversity/introprog-scalalib/introprog) 
+
+* Maven Central: [https://repo1.maven.org/maven2/se/lth/cs/introprog_3/](https://repo1.maven.org/maven2/se/lth/cs/introprog_3/)