rename mrb_atexit to mrb_state_atexit to clarify a func will be called at the...

rename mrb_atexit to mrb_state_atexit to clarify a func will be called at the end of state, not process; ref #2211

include/mruby.h

@@ -418,7 +418,7 @@ void* mrb_pool_realloc(struct mrb_pool*, void*, size_t oldlen, size_t newlen);
 mrb_bool mrb_pool_can_realloc(struct mrb_pool*, void*, size_t);
 void* mrb_alloca(mrb_state *mrb, size_t);
 
-void mrb_atexit(mrb_state *mrb, mrb_atexit_func func);
+void mrb_state_atexit(mrb_state *mrb, mrb_atexit_func func);
 
 #ifdef MRB_DEBUG
 #include <assert.h>

src/state.c

@@ -266,7 +266,7 @@ mrb_top_self(mrb_state *mrb)
 }
 
 void
-mrb_atexit(mrb_state *mrb, mrb_atexit_func f)
+mrb_state_atexit(mrb_state *mrb, mrb_atexit_func f)
 {
   size_t stack_size;
 

tasks/mrbgems.rake

@@ -34,7 +34,7 @@ MRuby.each_target do
         f.puts %Q[void]
         f.puts %Q[mrb_init_mrbgems(mrb_state *mrb) {]
         f.puts %Q[#{gems.map{|g| "GENERATED_TMP_mrb_%s_gem_init(mrb);" % g.funcname}.join("\n")}]
-        f.puts %Q[mrb_atexit(mrb, mrb_final_mrbgems);]
+        f.puts %Q[mrb_state_atexit(mrb, mrb_final_mrbgems);]
         f.puts %Q[}]
       end
     end