Another fix for !1452

Description

• Missing serial number bump
• $(top_srcdir) is Makefile, not shell, syntax
• top_srcdir not defined in configure.ac; srcdir is sufficient
• gnuscripts/reproducible-date was not included in distribution
• Check that configure_date is non-zero, raise error otherwise

Closes #389 (closed)

API Changes and Justification

Backwards Compatible Changes

• This change introduces no API changes
• This change adds new API calls

Backwards Incompatible Changes

• This change modifies an existing API
• This change removes an existing API

Review Status

N/A