added validators

app/main/views/validators.py

+from app.main import main
+from app.main.utils.common import response_message
+from flask import json
+from rulemall.validators import *
+
+
+@main.route('/validators', methods=['GET', 'POST'])
+def validators():
+    vals = []
+    for val in [Range, Length, Category, Regex, Missing, Unique, Empty]:
+        v = val()
+        vals.append(json.loads(str(v)))
+    return response_message(vals)
+
+
+@main.route('/validators/<val>', methods=['GET', 'POST'])
+def get_validator(val):
+    dct = {'Range': Range, 'Length': Length, 'Category': Category, 'Regex': Regex, 'Missing': Missing, 'Unique': Unique,
+           'Empty': Empty}
+    v = dct[val]()
+    return response_message(json.loads(str(v)))
+
+