Add ruby patch for statically linking zlib extension

patches/ruby/static_zlib.patch

@@ -0,0 +1,43 @@
+--- a/common.mk
++++ b/common.mk
+@@ -95,6 +95,7 @@ COMMONOBJS    = array.$(OBJEXT) \
+ 		vm_trace.$(OBJEXT) \
+ 		thread.$(OBJEXT) \
+ 		cont.$(OBJEXT) \
++		ext/zlib/zlib.$(OBJEXT) \
+ 		$(BUILTIN_ENCOBJS) \
+ 		$(BUILTIN_TRANSOBJS) \
+ 		$(MISSING)
+diff --git a/ruby-2.1.5.orig/configure b/ruby-2.1.5/configure
+index d0f1f68..45ab642 100755
+--- a/configure
++++ b/configure
+@@ -2838,6 +2838,8 @@ ac_configure="$SHELL $ac_aux_dir/configure"  # Please don't use this var.
+ 
+ 
+ 
++LIBS="$LIBS -lz"
++
+ { # environment section
+ 
+ 
+--- a/configure.in
++++ b/configure.in
+@@ -31,6 +31,8 @@ rm() {
+ }
+ ])])])
+ 
++LIBS="$LIBS -lz"
++
+ { # environment section
+ 
+ AC_ARG_WITH(baseruby,
+--- a/inits.c
++++ b/inits.c
+@@ -61,5 +61,6 @@ rb_call_inits(void)
+     CALL(Complex);
+     CALL(version);
+     CALL(vm_trace);
++    CALL(zlib);
+ }
+ #undef CALL