Makefile: use "generate-perl.sh" to massage Perl library

Extend "generate-perl.sh" such that it knows to also massage the Perl
library files. There are two major differences:

  - We do not read in the Perl header. This is handled by matching on
    whether or not we have a Perl shebang.

  - We substitute some more variables, which we read in via our
    GIT-BUILD-OPTIONS.

Adapt both our Makefile and the CMake build instructions to use this.

Signed-off-by: Patrick Steinhardt <ps@pks.im>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

generate-perl.sh

@@ -18,10 +18,20 @@ OUTPUT="$5"
 . "$GIT_VERSION_FILE"
 
 sed -e '1{' \
+    -e "	/^#!.*perl/!b" \
     -e "	s|#!.*perl|#!$PERL_PATH|" \
     -e "	r $PERL_HEADER" \
     -e '	G' \
     -e '}' \
-    -e "s/@GIT_VERSION@/$GIT_VERSION/g" \
+    -e "s|@GIT_VERSION@|$GIT_VERSION|g" \
+    -e "s|@LOCALEDIR@|$PERL_LOCALEDIR|g" \
+    -e "s|@NO_GETTEXT@|$NO_GETTEXT|g" \
+    -e "s|@NO_PERL_CPAN_FALLBACKS@|$NO_PERL_CPAN_FALLBACKS|g" \
     "$INPUT" >"$OUTPUT"
-chmod a+x "$OUTPUT"
+
+case "$INPUT" in
+*.perl)
+	chmod a+x "$OUTPUT";;
+*)
+	;;
+esac