rebuild patch queue from patch-queue branch

added patches:
0072-fix-building-with-gcc-4.6-Add-constructor-to-placate.patch
0073-fix-building-with-gcc-4.6-os2.cc-missing-include-cst.patch
0074-Add-constructor-for-nsCaseInsensitiveStringComparato.patch
0075-Add-constructor-for-nsXULAppInfo-which-inherits-from.patch
0076-Add-constructor-for-GTKEmbedDirectoryProvider.patch

modified patches:
0056-Disable-APNG-support-when-system-libpng-doesn-t-supp.patch

obsolete patches (fixed upstream):
0051-Do-exec-instead-of-uselessly-forking-in-xulrunner-la.patch
0072-Add-support-for-libnotify-0.7.patch

Closes: #624969