Tighten workflow

Hello. I tightened up the workflow a bit.

*  The scripts run straight from the php files. They no longer need to be pasted into the workflow.
* Added functions to make output UTF-8 safe. Previously, when garbage characters were passed in, Alfred would ignore all results.
* Added a [unicode normalization script](http://www.alfredforum.com/topic/2015-encoding-issue/#entry11272) written by the author of Alfred. This fixes a problem where accented letters like é would be split up into a regular e and an accent character.
* Removed the utf-8 encode and decode functions. Alfred I/O is always UTF-8, so there's no way to get input or output with other encodings. Previously, the utf-8 encode function was treating the input as ISO-8859-1 even though it was UTF-8, and then applying the transformation anyway, mangling the text. The utf-8 decode could unmangle the text, but it was just reversing an encoding error, not converting between standard formats.
* The html encode/decode have been adjusted to round trip cleanly.

In my testing, it solves both of these issues: https://github.com/willfarrell/alfred-encode-decode-workflow/issues/1 and https://github.com/willfarrell/alfred-encode-decode-workflow/issues/2