libview: Use GSlice to allocate EvViewSelection

These structs are allocated and deallocated a lot while selecting text
and merging selection regions.
libview: Use prepend + reverse instead of append to create selections list
libview: Do not schedule a redraw when selecting all text

merge_selection_region already invalidates the damaged region.
Updated Kazakh translation
libview: Fix a crash when selecting more than one page

https://bugzilla.gnome.org/show_bug.cgi?id=702874