CLEANUP: assorted typo fixes in the code and comments

This is 17th iteration of typo fixes
diff --git a/src/ssl_ckch.c b/src/ssl_ckch.c
index 6932526..f9b8f18 100644
--- a/src/ssl_ckch.c
+++ b/src/ssl_ckch.c
@@ -1402,7 +1402,7 @@
 						int i;
 
 						/* The certificate update on the server side (backend)
-						 * can be done by rewritting a single pointer so no
+						 * can be done by rewriting a single pointer so no
 						 * locks are needed here. */
 						/* free the server current SSL_CTX */
 						SSL_CTX_free(ckchi->server->ssl_ctx.ctx);