Merge pull request #2941 from Mav7/master

Added range.h.md and edited re.h.md and version.h.md

doc/api/mruby/range.h.md

+#### mrb_range_new
+```C
+  mrb_value mrb_range_new(mrb_state*, mrb_value, mrb_value, mrb_bool);
+```
+Initializes a Range. The first mrb_value being the beginning value and second being the ending value.
+The third parameter is an mrb_bool value that represents the inclusion or exclusion of the last value.
+If the third parameter is 0 then it includes the last value in the range. If the third parameter is 1 
+then it excludes the last value in the range.
+C code
+```C
+  #include <stdio.h>
+  #include <mruby.h>
+  #include "mruby/range.h" // Needs the range header.
+  #include "mruby/compile.h"
+
+  int main(int argc, char *argv[])
+    {
+      mrb_int beg = 0;
+      mrb_int end = 2;
+      mrb_bool exclude = 1;
+      mrb_value range_obj;
+      mrb_state *mrb = mrb_open();
+      if (!mrb) { /* handle error */ }
+      FILE *fp = fopen("test.rb","r");
+      range_obj = mrb_range_new(mrb, mrb_fixnum_value(beg), mrb_fixnum_value(end), exclude);
+      mrb_value obj = mrb_load_file(mrb,fp);
+      mrb_funcall(mrb, obj, "method_name", 1, range_obj);
+      fclose(fp);
+      mrb_close(mrb);
+      return 0;
+    }
+```
+Ruby code
+```Ruby
+  class Example_Class
+    def method_name(a)
+      puts a
+      puts a.class
+    end
+  end
+  Example_Class.new
+```
+This returns the following:
+```Ruby
+  0...2
+  Range
+```

doc/api/mruby/re.h.md

-#### Macros
-### REGEXP_CLASS
+### Macros
+#### REGEXP_CLASS
 A string with the name of the REGEXP class.

doc/api/mruby/version.h.md

-#### Macros
-### MRUBY_RUBY_VERSION
+### Macros
+#### MRUBY_RUBY_VERSION
 The version of Ruby used by mruby.
-### MRUBY_RUBY_ENGINE
+#### MRUBY_RUBY_ENGINE
 Ruby engine.
-### MRUBY_VERSION
+#### MRUBY_VERSION
 The mruby version.
-### MRUBY_RELEASE_MAJOR
+#### MRUBY_RELEASE_MAJOR
 Major release version.
-### MRUBY_RELEASE_MINOR
+#### MRUBY_RELEASE_MINOR
 Minor release version.
-### MRUBY_RELEASE_NO
+#### MRUBY_RELEASE_NO
 Release number.
-### MRUBY_RELEASE_DATE
+#### MRUBY_RELEASE_DATE
 Release date as a string.
-### MRUBY_RELEASE_YEAR
+#### MRUBY_RELEASE_YEAR
 Release year.
-### MRUBY_RELEASE_MONTH
+#### MRUBY_RELEASE_MONTH
 Release month.
-### MRUBY_RELEASE_DAY
+#### MRUBY_RELEASE_DAY
 Release day.
-### MRUBY_BIRTH_YEAR
+#### MRUBY_BIRTH_YEAR
 The year mruby was first created.
-### MRUBY_AUTHOR
+#### MRUBY_AUTHOR
 Mruby's authors.
-### MRB_STRINGIZE0(expr)
+#### MRB_STRINGIZE0(expr)
 A passed in expression.
-### MRB_STRINGIZE(expr)
+#### MRB_STRINGIZE(expr)
 Passes in an expression to MRB_STRINGIZE0.
-### MRUBY_DESCRIPTION
+#### MRUBY_DESCRIPTION
 mruby's version, and release date.
-### MRUBY_COPYRIGHT
+#### MRUBY_COPYRIGHT
 mruby's copyright information.