FreeRTOS Kernel Spelling Update (#170)

* FreeRTOS Kernel Spelling Update

* Added spell check to kernel repository.
* Fixed small spelling errors in various kernel source files.
* Added documentation for spellcheck.

Note: Only kernel files are checked for spelling, and portable files are ignored.

diff --git a/include/queue.h b/include/queue.h
index 712943a..53b6231 100644
--- a/include/queue.h
+++ b/include/queue.h
@@ -1535,7 +1535,7 @@
 #endif
 
 /*
- * Generic version of the function used to creaet a queue using dynamic memory
+ * Generic version of the function used to create a queue using dynamic memory
  * allocation.  This is called by other functions and macros that create other
  * RTOS objects that use the queue structure as their base.
  */
@@ -1546,7 +1546,7 @@
 #endif
 
 /*
- * Generic version of the function used to creaet a queue using dynamic memory
+ * Generic version of the function used to create a queue using dynamic memory
  * allocation.  This is called by other functions and macros that create other
  * RTOS objects that use the queue structure as their base.
  */