Fix version number of gRPC.podspec

And solves a few linter issues that prevent it from being submitted to Cocoapods' repo.

gRPC.podspec

 Pod::Spec.new do |s|
   s.name     = 'gRPC'
-  s.version  = '0.0.1'
-  s.summary  = 'Generic gRPC client library for iOS/OSX'
-  s.homepage = 'https://www.grpc.io'
+  s.version  = '0.5.1'
+  s.summary  = 'gRPC client library for iOS/OSX'
+  s.homepage = 'http://www.grpc.io'
   s.license  = 'New BSD'
-  s.authors  = { 'Jorge Canizales' => 'jcanizales@google.com',
-                 'Michael Lumish'  => 'mlumish@google.com' }
+  s.authors  = { 'The gRPC contributors' => 'grpc-packages@google.com' }
 
-  # s.source = { :git => 'https://github.com/grpc/grpc.git',  :tag => 'release-0_5_0' }
+  # s.source = { :git => 'https://github.com/grpc/grpc.git',
+  #              :tag => 'release-0_9_1-objectivec-0.5.1' }
 
   s.ios.deployment_target = '6.0'
   s.osx.deployment_target = '10.8'
@@ -15,7 +15,6 @@ Pod::Spec.new do |s|
 
   s.subspec 'RxLibrary' do |rs|
     rs.summary  = 'Reactive Extensions library for iOS.'
-    rs.authors  = { 'Jorge Canizales' => 'jcanizales@google.com' }
 
     rs.source_files = 'src/objective-c/RxLibrary/*.{h,m}',
                       'src/objective-c/RxLibrary/transformations/*.{h,m}',
@@ -25,16 +24,13 @@ Pod::Spec.new do |s|
 
   s.subspec 'C-Core' do |cs|
     cs.summary  = 'Core cross-platform gRPC library, written in C.'
-    cs.authors = { 'Craig Tiller'   => 'ctiller@google.com',
-                   'David Klempner' => 'klempner@google.com',
-                   'Nicolas Noble'  => 'nnoble@google.com',
-                   'Vijay Pai'      => 'vpai@google.com',
-                   'Yang Gao'       => 'yangg@google.com' }
 
     cs.source_files = 'src/core/**/*.{h,c}', 'include/grpc/*.h', 'include/grpc/**/*.h'
     cs.private_header_files = 'src/core/**/*.h'
     cs.header_mappings_dir = '.'
-    cs.xcconfig = { 'HEADER_SEARCH_PATHS' => '"$(PODS_ROOT)/Headers/Build/gRPC" "$(PODS_ROOT)/Headers/Build/gRPC/include"' }
+    cs.xcconfig = { 'HEADER_SEARCH_PATHS' => '"$(PODS_ROOT)/Headers/Build/gRPC" '
+                                             '"$(PODS_ROOT)/Headers/Build/gRPC/include"' }
+    cs.compiler_flags = '-GCC_WARN_INHIBIT_ALL_WARNINGS', '-w'
 
     cs.requires_arc = false
     cs.libraries = 'z'
@@ -67,8 +63,6 @@ Pod::Spec.new do |s|
 
   s.subspec 'GRPCClient' do |gs|
     gs.summary = 'Objective-C wrapper around the core gRPC library.'
-    gs.authors  = { 'Jorge Canizales' => 'jcanizales@google.com',
-                    'Michael Lumish'  => 'mlumish@google.com' }
 
     gs.source_files = 'src/objective-c/GRPCClient/*.{h,m}',
                       'src/objective-c/GRPCClient/private/*.{h,m}'
@@ -85,7 +79,6 @@ Pod::Spec.new do |s|
 
   s.subspec 'ProtoRPC' do |ps|
     ps.summary  = 'RPC library for ProtocolBuffers, based on gRPC'
-    ps.authors  = { 'Jorge Canizales' => 'jcanizales@google.com' }
 
     ps.source_files = 'src/objective-c/ProtoRPC/*.{h,m}'