patch 8.2.3749: error messages are everywhere

Problem:    Error messages are everywhere.
Solution:   Move more error messages to errors.h and adjust the names.
diff --git a/src/getchar.c b/src/getchar.c
index bdf0272..8c6b48d 100644
--- a/src/getchar.c
+++ b/src/getchar.c
@@ -1010,7 +1010,7 @@
 	if (typebuf.tb_len > 2147483647 - extra)
 	{
 	    // string is getting too long for a 32 bit int
-	    emsg(_(e_toocompl));    // also calls flush_buffers
+	    emsg(_(e_command_too_complex));    // also calls flush_buffers
 	    setcursor();
 	    return FAIL;
 	}