Instead of having a few different mutually exclusive booleans it
makes sense to have it be a mode with the following options:
automatic, single, dual.

This allows us to have a way to automatically determine if dual page
mode should be used when the window is large enough.

https://bugzilla.gnome.org/show_bug.cgi?id=689468
origin commit:
https://git.gnome.org/browse/evince/commit/?h=gnome-3-10&id=42f6d4b

This "Automatic" zoom mode will use fit width when
the window is smaller than 100% of the actual page size
and then use the actual page size up to the point the
window is large enough to hold two entire pages side
by side.

https://bugzilla.gnome.org/show_bug.cgi?id=689468
origin commit:
https://git.gnome.org/browse/evince/commit/?h=gnome-3-10&id=0cad875

https://bugzilla.gnome.org/show_bug.cgi?id=689468
origin commit:
https://git.gnome.org/browse/evince/commit/?h=gnome-3-10&id=ffd3853

taken from:
https://git.gnome.org/browse/evince/commit/?id=1346a98

- Modified configure.ac to use both webkit2 and webkit1 based on gtk version
- Modified Automake file in help/reference/shell/Makefile.am to compile with gtk-doc
- Modified ev-document-model to support epub-documents.
- Modified ev-window for epub documents.
- Modified jobs so epub pages are not rendered.
- Modified ev-document, although I'm not sure if this is necessary.

Still need to figure out where the web view load uri has to be called to actually load pages, from there the puzzle would be much simpler. Hope to get this done in the week, and pick up the pace now that only six weeks of coding remain before final evaluation.