Improve build system

- Reduce full build latency from ~20s to ~18s
- Bring back silent mode if `make V=0` is passed
- Demodernize utimes() polyfill so it works RHEL5
- Delete some old shell scripts that are no longer needed
- Truncate long lines when outputting builds to Emacs buffers

libc/calls/utimensat-nt.c

@@ -32,7 +32,7 @@
 #include "libc/time/time.h"
 
 textwindows int sys_utimensat_nt(int dirfd, const char *path,
-                             const struct timespec ts[2], int flags) {
+                                 const struct timespec ts[2], int flags) {
   int i, rc;
   int64_t fh;
   uint16_t path16[PATH_MAX];