CLEANUP: assorted typo fixes in the code and comments

These are mostly comments in the code. A few error messages were fixed
and are of low enough importance not to deserve a backport. Some regtests
were also fixed.
diff --git a/include/proto/log.h b/include/proto/log.h
index 6c96432..a2e9d47 100644
--- a/include/proto/log.h
+++ b/include/proto/log.h
@@ -172,13 +172,13 @@
 
 /*
  * Write a IP address to the log string
- * +X option write in hexadecimal notation, most signifant byte on the left
+ * +X option write in hexadecimal notation, most significant byte on the left
  */
 char *lf_ip(char *dst, const struct sockaddr *sockaddr, size_t size, const struct logformat_node *node);
 
 /*
  * Write a port to the log
- * +X option write in hexadecimal notation, most signifant byte on the left
+ * +X option write in hexadecimal notation, most significant byte on the left
  */
 char *lf_port(char *dst, const struct sockaddr *sockaddr, size_t size, const struct logformat_node *node);