configure: Improves GLES 1.x checks
configure: Improves GLES 1.x checks

We now always aim to use pkg-config based configuration when possible,
but when not configure.ac now knows the difference between GLES_CM
libraries that contain EGL symbols (I.e. a separate EGL library doesn't
need to be found) and GLESv1_CM libraries that don't contain EGL
symbols.

http://bugzilla.clutter-project.org/show_bug.cgi?id=2160

djdeath/clutter-multithreaded,spatulasnout/clutter,ebassi/clutter,Distrotech/clutter,Distrotech/clutter,rkudiyarov/clutter_osx,nobled/clutter,GNOME/clutter,rkudiyarov/clutter_osx,jigpu/clutter,collects/clutter,Distrotech/clutter,dlespiau/clutter,ebassi/clutter,heysion/clutter-clone,GNOME/clutter,rkudiyarov/clutter_osx,spatulasnout/clutter,heysion/clutter-clone,djdeath/clutter,kerrickstaley/clutter-vala,rkudiyarov/clutter_osx,ebassi/clutter,jigpu/clutter,nobled/clutter,kerrickstaley/clutter-vala,jigpu/clutter,Distrotech/clutter,collects/clutter,Distrotech/clutter,dlespiau/clutter,djdeath/clutter-android,djdeath/clutter,djdeath/clutter-android,heysion/clutter-clone,nobled/clutter,spatulasnout/clutter,GNOME/clutter,spatulasnout/clutter,collects/clutter,djdeath/clutter-multithreaded,djdeath/clutter-android,spatulasnout/clutter,jigpu/clutter,jigpu/clutter,djdeath/clutter-android,djdeath/clutter-multithreaded,GNOME/clutter,Distrotech/clutter,djdeath/clutter,ebassi/clutter,jigpu/clutter,kerrickstaley/clutter-vala,djdeath/clutter,kerrickstaley/clutter-vala,dlespiau/clutter,djdeath/clutter-multithreaded,heysion/clutter-clone,GNOME/clutter,ebassi/clutter,djdeath/clutter,djdeath/clutter,djdeath/clutter-android,heysion/clutter-clone,collects/clutter,collects/clutter