* Add headings for each concrete and mix-in class and list methods and
  attributes under them
* Fix class and method cross references
* Changed RequestHandler to BaseRequestHandler and added class heading
* Pull out Stream/DatagramRequestHandler definitions
* Reordered the request handler setup(), handle(), finish() methods
* Document constructor parameters for the server classes
* Remove version 2.6 not relevant for Python 3 documentation

the same values as open().

Patch by Aviv Palivoda.

Patch from Chi Hsuan Yen.

versions 10.5 or higher.  Original patch by A. Jesse Jiryu Davis.

no ResourceWarning is emitted.

if the stack is too deep.

The original form is incorrect grammar and feels awkward, even though the
meaning is clear.

not have a math vocabulary.

when the iteration is finished, but when it was failed with error.

Based on patch by Guido van Rossum.

Fixed the documented about buffer overflow error for "es#" and "et#" format
units.

* Various sections were pointing to the section on the string.Formatter
  class, when the section on the common format string syntax is probably more
  appropriate
* Fix references to various format() functions and methods
* Nested replacement fields may contain conversions and format specifiers,
  and this is tested; see Issue #19729 for instance

Based on patches by Brian Brazil and Daniel Rocco.

Reported by Denis Akhiyarov on docs@

Reported by Jon Tetlak on docs@

Fixed a crash when unpickle the functools.partial object with wrong state.
Fixed a leak in failed functools.partial constructor.
"args" and "keywords" attributes of functools.partial have now always types
tuple and dict correspondingly.

Based on patch by Aviv Palivoda.

Patch written by Carlo Beccarini <hackdiablo.cb@gmail.com>.

Accept time delta up to 0.12 second, instead of 0.11, for the "AMD64 FreeBSD
9.x" buildbot slave.