More proofreading and minor revisions to Hugo docs

Hello Steve,

Note that I made changes to three files outside of the Hugo full documentation in this patch:

* README.md
* main.go
* docs/layouts/index.html

Please double check to make sure my changes are not too intrusive before merging this patch.  :-)

Among the various changes, most instances of

    {{ template "partials/FILE.html" . }}

were changed to

    {{ partial "FILE.html" . }}

Also, in main.go, change "2013" to "2013-14".