Provide some instructions in the README, remove stray code

README.md

@@ -24,6 +24,45 @@ The design, and implementation, will avoid overly-involved solutions. Ideally,
 any Haskeller should be able to pick up this project and know what's going on.
 This extends to documentation as well.
 
+## How do I use this?
+
+The executable (called `shields`) allows a range of command-line options, which
+can be viewed with `--help`. These are listed below:
+
+```
+Options:
+              --hostname=NAME          local hostname, default "localhost"
+  -b ADDRESS  --address=ADDRESS        address to bind to, default "0.0.0.0"
+  -p PORT     --port=PORT              port to listen on, default off
+              --ssl-address=ADDRESS    ssl address to bind to, default off
+              --ssl-port=PORT          ssl port to listen on, default off
+              --ssl-cert=PATH          path to ssl certificate in PEM format, default off
+              --ssl-chain-cert         certificate file contains complete certificate chain
+              --no-ssl-chain-cert      certificate file contains only the site certificate
+              --ssl-key=PATH           path to ssl private key in PEM format, default off
+              --access-log=PATH        access log, default log to file "log/access.log"
+              --error-log=PATH         error log, default log to file "log/error.log"
+              --no-access-log          don't have an access log
+              --no-error-log           don't have an error log
+  -c          --compression            use gzip compression on responses, default compressed
+  -t SECS     --timeout=SECS           set default timeout in seconds, default 60
+              --no-compression         serve responses uncompressed, default compressed
+  -v          --verbose                print server status updates to stderr, default True
+  -q          --quiet                  do not print anything to stderr, default verbose
+              --proxy=X_Forwarded_For  Set --proxy=X_Forwarded_For if your snap application 
+                                       is behind an HTTP reverse proxy to ensure that 
+                                       rqClientAddr is set properly.
+                                       Set --proxy=haproxy to use the haproxy protocol
+                                       (http://haproxy.1wt.eu/download/1.5/doc/proxy-protocol.txt)
+              --unix-socket=PATH       Absolute path to unix socket file. File will be removed if already exists
+              --unix-socket-mode=MODE  Access mode for unix socket in octal, for example 0760.
+                                        Default is system specific.
+  -h          --help                   display this help and exit
+```
+
+When run, the executable acts as an app server - send requests to it to get
+responses.
+
 ## What does this run on?
 
 Currently, our CI checks GHC 8.10.4, on each of the following platforms: