add devel/ponscripter-sekai port

[jbeich]

Summary

Add new port: devel/ponscripter-sekai

PR: 195799
Approved by: ??? (mentor)

Ponscripter is an interpreter for visual-novel-type games, derived from
the NScripter design but modified significantly to improve support for
Western languages (at the cost of diminished support for Japanese).

Ponscripter is a fork of ONScripter-En that drops any attempt to remain
in synch with the upstream source code, and instead concentrates on
providing the best possible support for Western languages. It is no
longer fully NScripter-compatible, but remains an easy target to port
NScripter games to when localising them.

This fork takes advantage of SDL2 and improves Steam integration.

WWW: https://github.com/sekaiproject/ponscripter-fork

Package description is ripped from the lengthy ponscripter(7) manpage rather than unmaintained WRKSRC/debian/control, GetDeb package or even Wikipedia.

No direct dependency on libpthread even among vendor LDFLAGS but it's pulled by sdl.pc and ignored by -Wl,--as-needed. Only -logg and -lvorbis are stripped. See poudriere logs.

The source can be built using base GCC with MMX/SSE2 optimizations disabled. But I'm trying to keep my sanity by not special-casing 8.x and non-x86. For a fragile example:

USES=		compiler ...

.include <bsd.port.options.mk>

.if ${ARCH} == amd64 || ${ARCH} == i386 || ${ARCH} == powerpc
USES+=		compiler:c++11-lang
.endif

.include <bsd.port.pre.mk>

.if ${CHOSEN_COMPILER_TYPE} == clang
CONFIGURE_ENV+=	CC_VER="4.8"
CONFIGURE_ARGS+=--unsupported-compiler
.endif

Test Plan

Runtime tested within 8.4R amd64 poudriere jail against games/narcissu2.

poudriere testport -P logs:
8.4R amd64
9.3R i386
10.0R amd64
10.1R i386
MANPAGES=off

$ portlint -AC
WARN: Makefile: [55]: use ${VARIABLE}, instead of $(VARIABLE).
0 fatal errors and 1 warning found.

[jbeich]

Closed by commit rP378798 (authored by @jbeich).