The original image was 2055px × 1252px, which was oversized
and did not fit the required dimension of 600px × 400px
(3:2 aspect ratio).
To fix, the image was cropped and resized to the required dimension,
and was further optimized:
$ pngquant --nofs -v --speed 1 --quality 65-80 shelan-tn.png
$ optipng -o7 -zm1-9 shelan-tn-or8.png
$ mv shelan-tn-or8.png shelan-tn.png
reducing its filesize from 334125 bytes to 26929 bytes.
See #1831
The common is the `where` func and this:
```
panic: reflect: call of reflect.Value.Type on zero Value [recovered]
panic: reflect: call of reflect.Value.Type on zero Value
```
There is no good reason to export all the template funcs:
* They're not used outside the templates.
* If usable in other packages, they should be moved (to helpers?)
* They create too broad an interface;
users of the tpl package don't see the forest for all the trees.
Add humanize (inflect.Humanize) to the template funcMap. Documentation and
tests are included.
Various code cleanups of the template funcs:
- Break pluralize and singularize out into stand-alone funcs.
- Sort the list of funcMap entries.
- Add some minimal godoc comments to all public funcs.
- Fix some issues found by golint and grind.
Started to increase coverage in helpers package, now at 74.9% of statements.
In the process, also a few minor changes have been applied to content.go.
* Content.go has undergone a formatting refactor regarding comments
* Unused function TruncateWords has been removed
* RenderingContext's "mmark" has been changed to use MmarkRender
* Content_test.go added to cover content.go's functionality
