Expand the OS X/Xcode gitignores

- Add the folder CocoaPods will add to the root folder.
- Move and expand the entries in the objectivec directory.

.gitignore

@@ -88,16 +88,14 @@ build_msvc
 # packages themselves.
 /csharp/src/packages/*/
 
-# Directories created by opening the Objective C Xcode projects.
-objectivec/ProtocolBuffers_OSX.xcodeproj/project.xcworkspace/xcuserdata/
-objectivec/ProtocolBuffers_OSX.xcodeproj/project.xcworkspace/xcshareddata/ProtocolBuffers_OSX.xccheckout
-objectivec/ProtocolBuffers_OSX.xcodeproj/xcuserdata/
-objectivec/ProtocolBuffers_iOS.xcodeproj/project.xcworkspace/xcuserdata/
-objectivec/ProtocolBuffers_iOS.xcodeproj/project.xcworkspace/xcshareddata/ProtocolBuffers_iOS.xccheckout
-objectivec/ProtocolBuffers_iOS.xcodeproj/xcuserdata/
 # OS X's Finder creates these for state about opened windows/etc.
 **/.DS_Store
 
+# Cocoapods artifacts
+# Podfile.lock and the workspace file are tracked, to ease deleting them. That's
+# needed to trigger "pod install" to rerun the preinstall commands.
+Pods/
+
 # Comformance test output
 conformance/.libs/
 conformance/com/

objectivec/.gitignore

+## Build generated
+build/
+DerivedData/
+
+## Various settings
+*.pbxuser
+!default.pbxuser
+*.mode1v3
+!default.mode1v3
+*.mode2v3
+!default.mode2v3
+*.perspectivev3
+!default.perspectivev3
+xcuserdata/
+
+## Other
+*.moved-aside
+*.xccheckout
+*.xcscmblueprint
+
+## Obj-C/Swift specific
+*.hmap
+*.ipa