Update INSTALL.adoc to provide extra help for those getting an error regarding yaml...

diff --git a/INSTALL.adoc b/INSTALL.adoc
index dc2fa2b45fd1196a64420422278cbca9db0f4e23..8a008d7b32960d3cf8dd0fb115808a4bf49f3670 100644 (file)
--- a/INSTALL.adoc
+++ b/INSTALL.adoc
@@ -32,6 +32,15 @@ ImportError: No module named yaml
 try editing make_dungeon.py to change `#!/usr/bin/env python` to
 read `#!/usr/bin/env python3`
 
+If you still get the error, use the following command to install yaml with pip:
+
+`pip install pyyaml`
+
+Make sure you have `pip` installed on your system.  If not, you should install it first:
+
+https://pip.pypa.io/en/stable/installing/
+
+
 4. Optionally run a regression test on the code with `make check`.
 
 5. Run `./advent` to play.