Fix Docker build instruction example

Dockerfile

@@ -1,6 +1,6 @@
 FROM perl:stable
 
-RUN cpan cpanm Config::Std \
+RUN   cpanm Config::Std \
    && cpanm Template \
    && cpanm Template::Plugin::DBI \
    && cpanm Template::Plugin::HTML::Strip \

GETTING_STARTED.md

@@ -80,12 +80,14 @@ in the directory from which the site-generator is run. There are two ways to mak
   ```-v <path to db directory>/hpr.db:/usr/src/app/hpr.db```
 
 Build the image by running the following command from the hpr_generator directory:
-```docker run -t hpr/site-generator .```
+```docker build -t hpr/site-generator .```
 
 The first build will take a while. It must pull down the base container, perl-latest, and then pull down and build the 
 various Perl modules from CPAN. After the initial build, if you have modified your site.cfg file, templates dir, or the 
 site-generator program itself, builds will be very quick.
 
+If the build fails, it is often from a CPAN module failing to download and install. Try running the Docker build command again.
+
 ## Running the container
 
 When runing the Docker image, your local output directory (typically public_html) must be mounted into the container using