Fix typos

Source/Classes/AnimatedImages/PINAnimatedImage.h

@@ -147,7 +147,7 @@ typedef void(^PINAnimatedImageInfoReady)(PINImage * _Nonnull coverImage);
  */
 @property (nonatomic, readonly) size_t frameCount;
 /**
- @abstract Return any error that has occured. Playback will be paused if this returns non-nil.
+ @abstract Return any error that has occurred. Playback will be paused if this returns non-nil.
  */
 @property (nonatomic, readonly, nullable) NSError *error;
 

Source/Classes/AnimatedImages/PINCachedAnimatedImage.h

@@ -58,7 +58,7 @@
  */
 @property (nonatomic, readonly) BOOL playbackReady;
 /**
- @abstract Return any error that has occured. Playback will be paused if this returns non-nil.
+ @abstract Return any error that has occurred. Playback will be paused if this returns non-nil.
  */
 @property (nonatomic, readonly) NSError *error;
 /**

Source/Classes/PINRemoteImageDownloadTask.m

@@ -96,7 +96,7 @@ - (BOOL)cancelWithUUID:(NSUUID *)UUID resume:(PINResume **)resume
     BOOL hasResume = resume != nil;
     [self.lock lockWithBlock:^{
         if (hasResume) {
-            //consider skipping cancelation if there's a request for resume data and the time to start the connection is greater than
+            //consider skipping cancellation if there's a request for resume data and the time to start the connection is greater than
             //the time remaining to download.
             NSTimeInterval timeToFirstByte = [[PINSpeedRecorder sharedRecorder] weightedTimeToFirstByteForHost:self->_progressImage.dataTask.currentRequest.URL.host];
             if (self->_progressImage.estimatedRemainingTime <= timeToFirstByte) {

Source/Classes/PINRemoteImageManager.m

@@ -124,7 +124,7 @@ @interface PINRemoteImageManager () <PINURLSessionManagerDelegate>
   PINOperationQueue *_concurrentOperationQueue;
   PINRemoteImageDownloadQueue *_urlSessionTaskQueue;
 
-  // Necesarry to have a strong reference to _defaultAlternateRepresentationProvider because _alternateRepProvider is __weak
+  // Necessary to have a strong reference to _defaultAlternateRepresentationProvider because _alternateRepProvider is __weak
   PINAlternateRepresentationProvider *_defaultAlternateRepresentationProvider;
   __weak PINAlternateRepresentationProvider *_alternateRepProvider;
   NSURLSessionConfiguration *_sessionConfiguration;
@@ -1045,7 +1045,7 @@ - (NSUUID *)prefetchImageWithURL:(NSURL *)url options:(PINRemoteImageManagerDown
                             inputUUID:nil];
 }
 
-#pragma mark - Cancelation & Priority
+#pragma mark - Cancellation & Priority
 
 - (void)cancelTaskWithUUID:(NSUUID *)UUID
 {

Source/Classes/PINSpeedRecorder.h

@@ -26,7 +26,7 @@ typedef enum : NSUInteger {
 /*
  Returns a weighted average of the bytes per second of a transfer with the time to first byte subtracted.
  More specifically, we get the time to first byte for every task that completes,
- subtract it from the total transfer time, calulate bytes per second
+ subtract it from the total transfer time, calculate bytes per second
  and add it to an existing average using exponential weighted average and adjusting
  for starting bias.
  This is all done on a per host basis.