Log Message:
gdbm: update to 1.19.

Version 1.19 - 2020-12-23

* Pre-read the memory mapped regions on systems that support it.

This speeds up operations on big databases.

* gdbmtool: tagged initialization of structured data

Initializers for structured data can be given in tagged form, e.g.:

   store somekey { status=2, id={a,u,x}, name="foo" }

* Bugfixes:

** Preserve locking type during database reorganization