* 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
This changes the main documentation, doc strings, source code comments, and a
couple error messages in the test suite. In some cases the word was removed
or edited some other way to fix the grammar.
With the creation of the 3.5 branch earlier in the process,
it is necessary to do some of the version bumps now rather than at
final release time (for example, the equivalent of the 3.4->3.5 bumps
in f2bf12fa22c1). (Some of those changes have already been made, for
example in 30f5e7ec6afe.)
The concept of .pyo files no longer exists. Now .pyc files have an
optional `opt-` tag which specifies if any extra optimizations beyond
the peepholer were applied.
