Version 4.3.6 contains mostly bugfixes, but there are some small
improvements.  No incompatibilities with previous versions are known.

Visible changes in the shell and its modules since 4.3.5 include the
following:

The parameter subscripting flag "e", which existed but had limited
usefulness, has been extended to allow reverse matching of strings instead
of patterns.  For example, "${array[(ie)*]}" substitutes the index of the
array element that contains the exact string "*".  In previous versions of
the shell a fairly hairy process was necessary to ensure pattern characters
were quoted.

The cd, chdir, pushd and popd builtins now take the option -q (quiet) which
avoids side effects when changing directories, suppressing the effect of
the chpwd function, the chpwd_functions array and printing of the directory
stack.  The last was already possible with the option PUSHD_SILENT, but in
previous versions of the shell there was no easy way of suppressing the
other side effects.
