Refactor pqHelpWindow to get rid of the QWebKit qt dependency

Instead of using a QWebView widget, we simply use a QTextBrowser instead.

Change-Id: Ia92ed84dbd5bc07b927f9597f421835e10e677a7
Remove index tab in help window

Change-Id: Icb0bff168b590bf3c034fffbab7ac3d4bd43755f
Fix documentation style so it can be loaded correctly in the help widget

QTextBrowser only supports a subset of the css tags, so we need to be
careful with the one used.

Change-Id: I2560fab92c8049a195a878731ea848064d1568e8
Fix Query Data html file

Remove weird characther from the html file

Change-Id: Ic26559daf12815e44a988b30713dc5c24624675d