Remove string.h in khash.h

include/mruby/khash.h

@@ -12,7 +12,6 @@ extern "C" {
 #endif
 
 #include <stdint.h>
-#include <string.h>
 
 typedef uint32_t khint_t;
 typedef khint_t khiter_t;

src/class.c

@@ -7,6 +7,7 @@
 #include "mruby.h"
 #include <stdarg.h>
 #include <ctype.h>
+#include <string.h>
 #include "mruby/class.h"
 #include "mruby/proc.h"
 #include "mruby/string.h"

tasks/mrbgems_test.rake

@@ -68,7 +68,7 @@ MRuby.each_target do
             f.puts %Q[    ]
             f.puts %Q[    while(mrb_test(val2)) {]
             f.puts %Q[      char *str = mrb_string_value_cstr(mrb2, &val2);]
-            f.puts %Q[      mrb_ary_push(mrb, ary1, mrb_str_new(mrb, str, strlen(str)));]
+            f.puts %Q[      mrb_ary_push(mrb, ary1, mrb_str_new_cstr(mrb, str));]
             f.puts %Q[      val2 = mrb_ary_shift(mrb2, ary2);]
             f.puts %Q[    }]
             f.puts %Q[  }]