Update text for default terms and condition field
Remove possibility to configure x_frame_option;

due to the need to embed svg and possbibly other html objects we need an x_frame_options == sameorigin
witrh this commit i've in addition removed the possibility to use the 'allow from' mode;
this mode is not supported by all browsers so that ikt may cause some vulnerabilities by eventually ends in allowing whatever location to embed globaleaks