scripts: Changed -~/--sleep -> -w/--wait to sleep after -k/--keep-open

This changes -w/--wait to sleep _after_ -k/--keep-open, instead of
including the time spent waiting on inotifywait in the sleep time.

1. It's easier, no need to keep track of when we started waiting.

2. It's simpler to reason about.

3. It trivially avoids the multiple wakeup noise that plagued
   watch.py + vim (vim likes to do a bunch of renaming and stuff when
   saving files, including the file 4913 randomly?)

   Avoiding this was previously impossible because -~/--sleep was
   effectively a noop when combined with -k/--keep-open.

---

Also renamed from -~/--sleep -> -w/--wait, which is a bit more intuitive
and avoids possible shell issues with -~.

To make this work, dropped the -w/--block-cycles shortform flag in
dbgtrace.py. It's not like this flag is ever used anyways.

Though at the moment this is ignoring the possible conflict with
-w/--word-bits...

scripts/tailpipe.py

@@ -152,7 +152,7 @@ def main(path='-', *,
         lines=5,
         cat=False,
         coalesce=None,
-        sleep=None,
+        wait=None,
         keep_open=False):
     lock = th.Lock()
     event = th.Event()
@@ -175,7 +175,7 @@ def main(path='-', *,
                 if not keep_open:
                     break
                 # don't just flood open calls
-                time.sleep(sleep or 2)
+                time.sleep(wait or 2)
 
         except FileNotFoundError as e:
             print("error: file not found %r" % path,
@@ -200,7 +200,7 @@ def main(path='-', *,
                 with lock:
                     ring.draw()
                 # sleep a minimum amount of time to avoid flickering
-                time.sleep(sleep or 0.01)
+                time.sleep(wait or 0.01)
         th.Thread(target=background, daemon=True).start()
 
         main_(ring)
@@ -240,7 +240,7 @@ if __name__ == "__main__":
             type=lambda x: int(x, 0),
             help="Number of lines to coalesce together.")
     parser.add_argument(
-            '-~', '--sleep',
+            '-w', '--wait',
             type=float,
             help="Seconds to sleep between draws, coalescing lines in "
                 "between.")