Fixes

[skip travis]

lectures/lecture09/README.md

@@ -1,6 +1,6 @@
 # Lecture 9: First steps in the shell
 
-**Erick Matsen ([@ematsen](https://twitter.com/ematsen), [matsen.group](https://matsen.group))**
+**Erick Matsen ([@ematsen](https://twitter.com/ematsen), [matsen.group](http://matsen.group))**
 
 ## Learning objectives
 
@@ -17,7 +17,7 @@ After this course, you should be able to:
 
 Everything you need is in this repository.
 
----
+## Tutorial
 
      _______     _______.  ______     ___      .______    _______
     |   ____|   /       | /      |   /   \     |   _  \  |   ____|
@@ -48,7 +48,7 @@ To get started, execute the following commands in your shell:
 
 
     ssh rhino
-    git clone git@github.com:fredhutchio/tfcb_2019.git
+    git clone https://github.com/fredhutchio/tfcb_2019.git
     cd tfcb_2019/lectures/lecture09
 
 Now you can start the first lesson by clicking on the `first-steps.md` link in the file list above and starting your adventure!

lectures/lecture09/directories/README.md

@@ -28,6 +28,7 @@ As I described before the beginning ("root") directory is called `/`.
 Remember how before we learned how to give an argument to the directory-listing command?
 Now give that command a part of your path, so see the list of files at various places in your directory hierarchy.
 
+
 ### Tree
 
 Of course, directories can be nested and so it's not always easy to get an overall view of what is where.
@@ -51,6 +52,21 @@ The `tree` command can also take an argument, which is the directory for which i
 * look in the `tree` documentation to list only directories and try that out here
 * try giving `cd` the name of a directory that doesn't exist or isn't a subdirectory of the current directory
 
+
+### Tab completion
+
+Experienced shell users do not write out the full names of files or directories.
+Instead, they use the tab key to have the shell complete file names for them.
+
+For example, try typing `ls seq` and then hitting the tab key.
+
+This also works to make your way through directories!
+Try `ls dir`, and tab.
+Now just hit tab a few more times.
+The shell should bring up some options, and you can select between them by typing the first letter or so and hitting tab again.
+Continue doing this until you run out of directories.
+
+
 ### Moving around more freely
 
 Try `cd`-ing into the `purchase` directory.