bidi.css is loaded when viewing LTR print view pages

If you view a topic and click 'print view' from the topic tools drop down, when the print template loads, the bidi.css file is loaded, this also happens when viewing the PM print view.

The bidi.css file only needs to be loaded when using RTL languages so an if statement to load the bidi.css file could be used, just like the one in the overall_header.html and simple_header.html templates.

Affected templates:

viewtopic_print.html / ucp_pm_viewmessage_print.html

Original code:

<link href="{T_THEME_PATH}/bidi.css" rel="stylesheet">

Could be:

<!-- IF S_CONTENT_DIRECTION eq 'rtl' -->

    <link href="{T_THEME_PATH}/bidi.css" rel="stylesheet">

<!-- ENDIF -->