Cannot install CT4E if GPE is already installed and vice versa (#1075)

* Cannot install CT4E if GPE is already installed

* 	Made all the plugins from the GPe update site incompatible with CT4E

features/com.google.cloud.tools.eclipse.suite.e45.feature/build.properties

@@ -12,4 +12,6 @@
 #  See the License for the specific language governing permissions and
 #  limitations under the License.
 ############################################################################
-bin.includes = feature.xml,feature.properties
+bin.includes = feature.xml,\
+               feature.properties,\
+               p2.inf

features/com.google.cloud.tools.eclipse.suite.e45.feature/p2.inf

@@ -0,0 +1,54 @@
+ requires.0.namespace = org.eclipse.equinox.p2.iu
+ requires.0.name = com.google.appengine.eclipse.sdkbundle.feature.feature.group
+ requires.0.min = 0
+ requires.0.max = 0
+
+ requires.1.namespace = org.eclipse.equinox.p2.iu
+ requires.1.name = com.google.appengine.eclipse.wtp.maven.feature.feature.group
+ requires.1.min = 0
+ requires.1.max = 0
+
+ requires.2.namespace = org.eclipse.equinox.p2.iu
+ requires.2.name = com.google.gdt.eclipse.suite.e44.feature.feature.group
+ requires.2.min = 0
+ requires.2.max = 0
+
+ requires.3.namespace = org.eclipse.equinox.p2.iu
+ requires.3.name = com.google.gdt.eclipse.mobile.android.feature.feature.group
+ requires.3.min = 0
+ requires.3.max = 0
+
+ requires.4.namespace = org.eclipse.equinox.p2.iu
+ requires.4.name = com.google.gwt.eclipse.sdkbundle.feature.feature.group
+ requires.4.min = 0
+ requires.4.max = 0
+
+ requires.5.namespace = org.eclipse.equinox.p2.iu
+ requires.5.name = com.android.ide.eclipse.adt.feature.feature.group
+ requires.5.min = 0
+ requires.5.max = 0
+
+ requires.6.namespace = org.eclipse.equinox.p2.iu
+ requires.6.name = com.android.ide.eclipse.ddms.feature.feature.group
+ requires.6.min = 0
+ requires.6.max = 0
+
+ requires.7.namespace = org.eclipse.equinox.p2.iu
+ requires.7.name = com.android.ide.eclipse.gldebugger.feature.feature.group
+ requires.7.min = 0
+ requires.7.max = 0
+
+ requires.8.namespace = org.eclipse.equinox.p2.iu
+ requires.8.name = com.android.ide.eclipse.hierarchyviewer.feature.feature.group
+ requires.8.min = 0
+ requires.8.max = 0
+
+ requires.9.namespace = org.eclipse.equinox.p2.iu
+ requires.9.name = com.android.ide.eclipse.ndk.feature.feature.group
+ requires.9.min = 0
+ requires.9.max = 0
+
+ requires.10.namespace = org.eclipse.equinox.p2.iu
+ requires.10.name = com.android.ide.eclipse.traceview.feature.feature.group
+ requires.10.min = 0
+ requires.10.max = 0