Fix two leaks caught be the newer Xcode analyzer

Source/GTMHTTPFetcher.m

@@ -253,6 +253,9 @@ - (void)dealloc {
   [initialRequestDate_ release];
   [comment_ release];
   [log_ release];
+  [allowedInsecureSchemes_ release];
+  // releaseCallbacks nilifies delegate_ making this release a no-op if releaseCallbacks was called
+  [delegate_ release];
 #if !STRIP_GTM_FETCH_LOGGING
   [redirectedFromURL_ release];
   [logRequestBody_ release];

Source/GTMHTTPFetcherService.m

@@ -71,6 +71,7 @@ - (void)dealloc {
   [credential_ release];
   [proxyCredential_ release];
   [authorizer_ release];
+  [allowedInsecureSchemes_ release];
 
   [super dealloc];
 }