pfSense

Add a space between interface name and mac address

Fix spaces

Show which is the invalid member on error message

Merge pull request #2398 from ExolonDX/branch_03

HTML Compliance - Services / DHCP Server

Bad character after <. Probable cause: Unescaped <. Try escaping it as <.
Ensure one machine's advskew < 20 (and the other is > 20).

Tidy up "status_rrd_graph.php"

- use Bootstrap class "img-responsive center-block" for images
(http://getbootstrap.com/css/#images)
- remove "name" attribute, invalid in HTML5

Merge pull request #2397 from ExolonDX/branch_02

Merge pull request #2396 from NOYB/GUI_Log_Entires_Placeholder

Merge pull request #2395 from NOYB/HTML_Compliance_-_Wizard_/_pfSense_Taffic_Shaper_/_

Merge duplicate CLASS statements

Remove duplicate class error by merging them together.