Document enumerator and rewording

examples/blame.c

@@ -148,7 +148,7 @@ static void usage(const char *msg, const char *arg)
 	fprintf(stderr, "   -L <n,m>            process only line range n-m, counting from 1\n");
 	fprintf(stderr, "   -M                  find line moves within and across files\n");
 	fprintf(stderr, "   -C                  find line copies within and across files\n");
-	fprintf(stderr, "   -F                  only care about the first parent\n");
+	fprintf(stderr, "   -F                  follow only the first parent commits\n");
 	fprintf(stderr, "\n");
 	exit(1);
 }

include/git2/blame.h

@@ -40,7 +40,8 @@ typedef enum {
 	 * commit (like `git blame -CCC`). Implies SAME_COMMIT_COPIES.
 	 * NOT IMPLEMENTED. */
 	GIT_BLAME_TRACK_COPIES_ANY_COMMIT_COPIES = (1<<3),
-
+	/** Restrict the search of commits to those reachable following only the
+	 * first parents. */
 	GIT_BLAME_FIRST_PARENT = (1<<4),
 } git_blame_flag_t;