use view settings() instead of loading it from preferences

[randy3k]

since the view settings may be different from the preferences

[phyllisstein]

Thanks for the pull request! It hadn't occurred to me that this setting would be propagated down to the view. I'll merge it on in with my gratitude.

[randy3k]

I notice it because my plugin Syntax Manager fails to work. Specifically, my settings is

{
    "syntaxmgr_settings":
    [ 
        {
            "scopes": ["text.html.markdown"],
            "settings":
            {
                "show_panel_on_build": false
            }
        }
   ]
}