Made manifests more compliant to the puppetlabs style guide

Before

puppet-lint * | wc -l
88

After

puppet-lint  --with-filename *
manifests/server.pp - WARNING: class not documented on line 1
manifests/init.pp - WARNING: class not documented on line 1
manifests/server/service.pp - WARNING: class not documented on line 1
manifests/server/subnet.pp - WARNING: selector inside resource block on line 30
manifests/server/subnet.pp - WARNING: defined type not documented on line 1
manifests/server/config.pp - WARNING: class not documented on line 1
manifests/server/host.pp - WARNING: selector inside resource block on line 23
manifests/server/host.pp - WARNING: defined type not documented on line 1
manifests/server/install.pp - WARNING: class not documented on line 1

Outstanding items are around documentation and selectors within resource blocks,
I felt this was beyond the scope of this simple update.
Updated README with style guide compliant examples

Corrected indentation and quotation.

ALso line 41 ended with a ";" rather than a ","
README correction on line 41

Missed correction of ";" to "," in previous commit
Merge pull request #3 from george-b/style-guide

Made manifests more compliant to the puppetlabs style guide