Fix error messages and more

PUBLISHED_FROM=11c57fc5ece01686e9cecab5e3bfce54a2825836

docs/c-api/util.h/mg_match_prefix.md

@@ -6,7 +6,7 @@ signature: |
   int mg_match_prefix(const char *pattern, int pattern_len, const char *str);
 ---
 
-Matches 0-terminated string (mg_match_prefix) or string with given length
+Match 0-terminated string (mg_match_prefix) or string with given length
 mg_match_prefix_n against a glob pattern.
-Match is case-insensitive. Returns the number of bytes matched or -1 if no match. 
+Match is case-insensitive. Return number of bytes matched, or -1 if no match. 
 

docs/c-api/util.h/mg_next_comma_list_entry.md

@@ -8,12 +8,12 @@ signature: |
 ---
 
 A helper function for traversing a comma separated list of values.
-It returns a list pointer shifted to the next value or NULL if the end
+It returns a list pointer shifted to the next value, or NULL if the end
 of the list found.
-The value is stored in a val vector. If the value has a form "x=y", then eq_val
-vector is initialised to point to the "y" part, and val vector length
+Value is stored in val vector. If value has form "x=y", then eq_val
+vector is initialized to point to the "y" part, and val vector length
 is adjusted to point only to "x".
-If the list is just a comma separated list of entries, like "aa,bb,cc" then
+If list is just a comma separated list of entries, like "aa,bb,cc" then
 `eq_val` will contain zero-length string.
 
 The purpose of this function is to parse comma separated string without