Ruby 1.8 compatible refactoring

Makes the workflow fully compatible with the system Ruby on OS X below 10.9 by

* removing *rb-appscript* dependency as it segfaults on OS X 10.8.5
* switching to *active-support* 3.2.x as version 4 is not supported for Ruby versions below < 1.9
* using *uuid-tools* to generate UUIDs as *securerandom* does not support this for Ruby versions below < 1.9
* reworking the bundled gem folder structure and loader to allow for Ruby versions specific loading (which prohibits direct inclusion of vendored Bundler dirs [contact me for a ZIP of the current structure])

It also addresses a number of issues I have found while testing the above, principally concerning empty and / or invalid last.fm data being returned and feedback about iTunes song retrieval, as well as performing basic localization (for numbers and dates only for now) and doing minor code cleanup. 

**Unluckily, this cannot be easily merged with the current master’s branch HEAD, as some of your refactoring breaks the above (notably, the switch to Ruby’s 1.9 hash declaration syntax in b4c4306e5629dd54040e265add7dca61a5ba4979 and 72d2fcddca54fc9292ef30599574367756266d2b).** If you want to pull, I suggest branching from fdc58fe9a32ef91e5174831759d155b8b1e20031 and merging/rebasing on that, then cherry picking your master commits.