contrib-autotools: Added some more details on how the sample works.
This is a project skeleton that uses criterion tests with the TAP test driver.
+## How this works
+
+Be sure to do the following to get similar setups to work:
+
+1. copy `tap-driver.sh` from your automake installation ([`autogen.sh:4-7`](autogen.sh#L4-L7)).
+2. create a wrapper script that contains the following ([`autogen.sh:12-15`](autogen.sh#L12-L15)):
+
+ ```bash
+ #!/bin/sh
+ $1 -Otap:- --always-succeed 2>&1 >/dev/null
+ ```
+
+3. Check for criterion ([`configure.ac:5-7`](configure.ac#L5-L7)).
+4. Check for awk ([`configure.ac:9`](configure.ac#L9)).
+5. Check for `tap-driver.sh` ([`configure.ac:14`](configure.ac#L14)).
+6. Set `LOG_COMPILER` to the path of the wrapper script created at step 2 ([`Makefile.am:2`](Makefile.am#L2)).
+7. Set `LOG_DRIVER` to a command running `tap-driver.sh` with our found awk ([`Makefile.am:5-6`](Makefile.am#L5-L6)).
+8. Register your test programs ([`Makefile.am:8-14`](Makefile.am#L8-L14)).
+
## Running the tests
The default setup assumes that criterion is installed on your system.
