Change MODRUBY_RUBY_ADJ to just replace a shebang in the first line

of the files, instead of all lines.  Additionally, loosen the regexp
slightly so that it handles more cases automatically.  This makes
ruby.port.mk's behavior similar to python.port.mk.

OK sthen@

lang/ruby/ruby.port.mk

@@ -1,4 +1,4 @@
-# $OpenBSD: ruby.port.mk,v 1.60 2013/03/20 19:13:50 jeremy Exp $
+# $OpenBSD: ruby.port.mk,v 1.61 2013/03/26 18:51:44 jeremy Exp $
 
 # ruby module
 
@@ -252,7 +252,10 @@ TEST_DEPENDS+=	${MODRUBY_RSPEC_DEPENDS}
 TEST_DEPENDS+=	${MODRUBY_RSPEC2_DEPENDS}
 .endif
 
-MODRUBY_RUBY_ADJ=	perl -pi -e 's,/usr/bin/env ruby,${RUBY},'
+MODRUBY_RUBY_ADJ =	perl -pi \
+		-e '$$. == 1 && s|^.*env ruby.*$$|\#!${RUBY}|;' \
+		-e '$$. == 1 && s|^.*bin/ruby.*$$|\#!${RUBY}|;' \
+		-e 'close ARGV if eof;'
 MODRUBY_ADJ_FILES?=
 .if !empty(MODRUBY_ADJ_FILES)
 MODRUBY_ADJ_REPLACE=	for pat in ${MODRUBY_ADJ_FILES:QL}; do \