patch 9.0.0828: various typos

Problem:    Various typos.
Solution:   Correct typos. (closes #11432)
diff --git a/src/blob.c b/src/blob.c
index 311b87e..bfc7723 100644
--- a/src/blob.c
+++ b/src/blob.c
@@ -716,7 +716,7 @@
 }
 
 /*
- * Implementaion of reduce() for Blob "argvars[0]" using the function "expr"
+ * Implementation of reduce() for Blob "argvars[0]" using the function "expr"
  * starting with the optional initial value "argvars[2]" and return the result
  * in "rettv".
  */