Trial: port some code to "use standard"

Just wanted to know how it feels to adapt code to use standard; 

I selected a small, unpublished module: Levenshtein::Simple. It's in the range of 530 lines of code without tests. A typical reinvent a better wheel, because Text::Levenshtein does not support arrays as input and misses an alignment method, which I needed in a simple and robust way.

Here the changes as diff:

49 changes, most of them explicit syntax for dereferencing.

2 barewords needed quoting: STDOUT, STDERR. But why are they there? They are not needed at all.

The nested ternary needed explicit braces. Now it's better readable.

1 LABEL not allowed as bareword. That's a bug of Guacamole. The label was a relict.

2 Invalid characters in the pod. Copy and paste of a reference. use standard; slurps the source as UTF-8 and it breaks. That's undocumented and the second bug. 

In summary simple changes and IMHO better readable now. Nice development tool but not ready for production.