Testing hhvm support with travis.
Code style change.

I like camelCase now instead of snake_case, for variables.  Times change.
Update README.md

Ditching bitdeli tracking bug.  Service didn't appear to work.
Issue #24 - Fixed a glitch in an error string.

Wasn't resolving unit name in the "unknown unit of measure" error message.
Update .travis.yml

Adding php 5.6 as an ok-to-fail test
add support for metres, and litres.
Merge pull request #25 from zomble/metre

Add support for metres, and litres (not a typo)
Ignore editor metadata files
comment cleanup