Fixed #5, when minlength and maxlength is string of number.
Fixed #6, add minlimit and maxlimit rule, and fixed minlength and maxlength rule.
fixed #6, add minlimit and maxlimit rule, test cases.
Update package version.
Merge 0.1.1 from develop branch, add minlimit, maxlimit, and fixed minlength, maxlength rule.