Re-organize directory structure (#4971)

See discussion in #2491

Co-authored-by: Ivan Levkivskyi <ilevkivskyi@dropbox.com>

stdlib/resource.pyi

@@ -0,0 +1,55 @@
+import sys
+from typing import NamedTuple, Tuple, overload
+
+RLIMIT_AS: int
+RLIMIT_CORE: int
+RLIMIT_CPU: int
+RLIMIT_DATA: int
+RLIMIT_FSIZE: int
+RLIMIT_MEMLOCK: int
+RLIMIT_NOFILE: int
+RLIMIT_NPROC: int
+RLIMIT_RSS: int
+RLIMIT_STACK: int
+RLIM_INFINITY: int
+RUSAGE_CHILDREN: int
+RUSAGE_SELF: int
+if sys.platform == "linux":
+    RLIMIT_MSGQUEUE: int
+    RLIMIT_NICE: int
+    RLIMIT_OFILE: int
+    RLIMIT_RTPRIO: int
+    RLIMIT_RTTIME: int
+    RLIMIT_SIGPENDING: int
+    RUSAGE_THREAD: int
+
+class _RUsage(NamedTuple):
+    ru_utime: float
+    ru_stime: float
+    ru_maxrss: int
+    ru_ixrss: int
+    ru_idrss: int
+    ru_isrss: int
+    ru_minflt: int
+    ru_majflt: int
+    ru_nswap: int
+    ru_inblock: int
+    ru_oublock: int
+    ru_msgsnd: int
+    ru_msgrcv: int
+    ru_nsignals: int
+    ru_nvcsw: int
+    ru_nivcsw: int
+
+def getpagesize() -> int: ...
+def getrlimit(__resource: int) -> Tuple[int, int]: ...
+def getrusage(__who: int) -> _RUsage: ...
+def setrlimit(__resource: int, __limits: Tuple[int, int]) -> None: ...
+
+if sys.platform == "linux":
+    @overload
+    def prlimit(pid: int, resource: int, limits: Tuple[int, int]) -> Tuple[int, int]: ...
+    @overload
+    def prlimit(pid: int, resource: int) -> Tuple[int, int]: ...
+
+error = OSError