Script to set us up for building all of our headers by themselves

[nmathewson]

This script makes a directory called "test_headers", then populates
it with one C file for each header. The C file defines all of the
*_PRIVATE macros listed in the header, and then includes the header.

The script also makes a Makefile in this directory that tries to
build every C file it generates.

This script is not production-ready: it does not handle out-of-tree
operation, and doesn't look at the flags actually set by autoconf.

[coveralls]

Pull Request Test Coverage Report for Build 7593

• 0 of 0 changed or added relevant lines in 0 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage remained the same at 63.015%

---

Totals
Change from base Build 7592:	0.0%
Covered Lines:	49557
Relevant Lines:	78643

---

💛 - Coveralls