Workaround for Qt 5 bug that causes text copied to the clipboard to be lost when quitting the viewer on windows.

https://bugreports.qt-project.org/browse/QTBUG-41125
Make the template used to create empty EPUB files customizable by the user
Metadata jacket: Allow customizing the jacket template to show the tags in alphabetical order
Refactor message box to not use uic to generate the UI

Also fixes incorrect resize of message box when toggling detailed
message.
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When removing a library from calibre, allow undoing the action
Replace gmail with gmx
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pep8
When detecting the encoding of HTML documents, if the document contains multiple charset declarations, prefer the HTML 5 syntax to the HTML 4 syntax. Fixes #1364961 [Unicode Conversion on Amazon after Release 2.x](https://bugs.launchpad.net/calibre/+bug/1364961)
Make requests available on file hosting servers