minor: remove unused SCRIPTISH_CONFIG_XML constant
Check for Ci.nsIPrivateBrowsingChannel in GM_xhr

Closes GH-147
Add additional protocols to GM_xhr whitelist

 - data: should be unproblematic to access. Already accessible through
   other means.
 - blob: should be unproblematic to access. Already accessible through
   other means (FileReader, etc).
Add first GM_xhr tests
Closes #161 Force use of HTTPS on userscripts.org
moving commonjs files to a separate folder
Closes #160 Ignoring @requires from usocheckup.dune.net (which are old school update scripts)
Closes #153 Making document-end the new default for new scripts created by Scriptish
Removing hidden @applybackgroundupdates
Closes #154 Reduce `throw new Error` to `throw Error`
Closes #106 offer an opt-out for the install detection so that GM and Scriptish can be used together
Script._file has no setter
Closes #135 Making sure that only a single USO data request is made at a time
Adding 167885 to uso block list
Closes #159 Replacing the Install button with a Blocked button that does nothing, for blocked scripts on USO
Merge branch 'master' of github.com:scriptish/scriptish
Closes #59 Chinese chars in the @name are supported
Closes #165 == -> = and removing the staging build
Closes #167 adding an undo secondary action to the door hanger displayed when installing an userscript
Closes #164 adding @grant unsafeWindow