CLEANUP: assorted typo fixes in the code and comments

This is 32nd iteration of typo fixes
diff --git a/src/hlua.c b/src/hlua.c
index 9b646bc..b8f727f 100644
--- a/src/hlua.c
+++ b/src/hlua.c
@@ -3966,7 +3966,7 @@
 		else
 			HLUA_SET_WAKEREQWR(hlua);
 
-		/* Otherwise, we can yield waiting for new data in the inpout side. */
+		/* Otherwise, we can yield waiting for new data in the input side. */
 		MAY_LJMP(hlua_yieldk(L, 0, 0, hlua_channel_forward_yield, TICK_ETERNITY, 0));
 	}