Tidy up HTML Colour Names

With XHTML 1.0, the extended colour names are invalid, to make pfSense
as W3C compliant as possible, need to go back to using the HEX code.
Merge pull request #335 from ExolonDX/a0c0e8aefbac3e3979bac5fbfdecfedfe49cc2d3

Tidy up HTML Colour Names
Validate passed parameters to smart commands, and the target device. Also escape when used in shell commands even after validation.
Discovered-By: Bernhard Thaler
Preserve "Idle timeout" parameter on interfaces gui. It fixes a problem pointed out on ticket #2641
Fix build list of widgets

Only consider files ending in ".php" to restrict widgets and avoid load
wrong files. It should fix #2761
Revert part of 0ff214f27d that was committed accidentally