Move inheritance expansion code into its own file

This commit moves expand_inherited_tables and underlings from
optimizer/prep/prepunionc.c to optimizer/utils/inherit.c.
Also, all of the AppendRelInfo-based expression manipulation routines
are moved to optimizer/utils/appendinfo.c.

No functional code changes.  One exception is the introduction of
make_append_rel_info, but that's still just moving around code.

Also, stop including <limits.h> in prepunion.c, which no longer needs
it since 3fc6e2d7f5b6.  I (Álvaro) noticed this because Amit was copying
that to inherit.c, which likewise doesn't need it.

Author: Amit Langote
Discussion: https://postgr.es/m/[email protected]

0 files changed, 0 insertions, 0 deletions