Removed the non-ASCII '–' character within the license part which causi…

[hKyo89]

Problem:
Found an error when compiling scss on Shopify with the following error message:

SCSS file is not UTF-8 encoded

The non-ASCII character resulting Shopify to fail compiling the whole scss files and giving you a failed-compiled output file as shown below on Chrome:

Root cause:
Results of the non-ASCII character found inside the the less directory (as the error occurred only for scss on Shopify):

The character:

Results of files inside src directory containing the character:

Solution:
Removed the non-ASCII '–' em-dash(??) character within the license part of every occurring file at the line of:

* Copyright (c) 2013–2015 Brian Reavis & contributors

[coveralls]

Changes Unknown when pulling 97b352c on hKyo89:master into * on selectize:master*.

[joallard]

Dup #1092. The character is valid UTF-8, and compilation using latest Less works.