Improve docs for pstat module and profile.

Clarify that methods takes a string which is interpreted as a re, and
not a re object.

Clarify what the old `-1`, `0`, `1` and `2` option were.

Author: Carreau

Doc/library/profile.rst

@@ -444,7 +444,7 @@ Analysis of the profiler data is done using the :class:`~pstats.Stats` class.
       significant entries.  Initially, the list is taken to be the complete set
       of profiled functions.  Each restriction is either an integer (to select a
       count of lines), or a decimal fraction between 0.0 and 1.0 inclusive (to
-      select a percentage of lines), or a regular expression (to pattern match
+      select a percentage of lines), or a string that will interpreted as a regular expression (to pattern match
       the standard name that is printed.  If several restrictions are provided,
       then they are applied sequentially.  For example::
 

Lib/pstats.py

@@ -48,7 +48,7 @@ class Stats:
     printed.
 
     The sort_stats() method now processes some additional options (i.e., in
-    addition to the old -1, 0, 1, or 2).  It takes an arbitrary number of
+    addition to the old -1, 0, 1, or 2 that are respectively  interpreted as 'stdname', 'calls', 'time', and 'cumulative').  It takes an arbitrary number of
     quoted strings to select the sort order.  For example sort_stats('time',
     'name') sorts on the major key of 'internal function time', and on the
     minor key of 'the name of the function'.  Look at the two tables in