Replaced RegExp method parser with recursive descent

Summary:
public

This diff replaces the RegEx module method parser with a handwritten recursive descent parser that's faster and easier to maintain.

The new parser is ~8 times faster when tested on the UIManager.managerChildren() method, and uses ~1/10 as much RAM.

The new parser also supports lightweight generics, and is more tolerant of white space.

(This means that you now can – and should – use types like `NSArray<NSString *> *` for your exported properties and method arguments, instead of `NSStringArray`).

Reviewed By: jspahrsummers

Differential Revision: D2736636

fb-gh-sync-id: f6a11431935fa8acc8ac36f3471032ec9a1c8490

Libraries/Network/RCTNetworking.m

@@ -56,7 +56,7 @@ static NSString *RCTGenerateFormBoundary()
   return [[NSString alloc] initWithBytesNoCopy:bytes length:boundaryLength encoding:NSUTF8StringEncoding freeWhenDone:YES];
 }
 
-- (RCTURLRequestCancellationBlock)process:(NSDictionaryArray *)formData
+- (RCTURLRequestCancellationBlock)process:(NSArray<NSDictionary *> *)formData
                                  callback:(RCTHTTPQueryResult)callback
 {
   RCTAssertThread(_networker.methodQueue, @"process: must be called on method queue");
@@ -289,7 +289,7 @@ RCT_EXPORT_MODULE()
       }
     };
   }
-  NSDictionaryArray *formData = [RCTConvert NSDictionaryArray:query[@"formData"]];
+  NSArray<NSDictionary *> *formData = [RCTConvert NSDictionaryArray:query[@"formData"]];
   if (formData) {
     RCTHTTPFormDataHelper *formDataHelper = [RCTHTTPFormDataHelper new];
     formDataHelper.networker = self;

Libraries/Settings/RCTSettingsManager.m

@@ -90,7 +90,7 @@ RCT_EXPORT_METHOD(setValues:(NSDictionary *)values)
 /**
  * Remove some values from the settings.
  */
-RCT_EXPORT_METHOD(deleteValues:(NSStringArray *)keys)
+RCT_EXPORT_METHOD(deleteValues:(NSArray<NSString *> *)keys)
 {
   _ignoringUpdates = YES;
   for (NSString *key in keys) {