Adds SDKMan so we can install Kotlin

removes JAVA_HOME as its now managed by SDKMAN

scripts/update_git.sh

@@ -1,12 +1,5 @@
 #!/bin/bash
 
-echo "This is where we update Git!"
-
-cd ~/Projects
-
-cd dfr
-git pull
-cd ../geeklib
-git pull
-cd ../lilith
-git pull
+cd ~/Projects/dfr && git fetch --all
+cd ~/Projects/geeklib && git fetch --all
+cd ~/Projects/lilith && git fetch --all