add README.md

README.md

+# JSON Schema form generator RenderJS gadget
+
+## Structure
+
+**Gadget for recursive load schema**
+
+[gadget_demo_json_schema_form.html](gadget_demo_json_schema_form.html)
+
+* **done** remove jquery dependence
+
+**Gadget for recursive form generation**
+
+[gadget_json_generated_form.html](gadget_json_generated_form.html)
+
+* **done** remove slapos specific code
+* **partly done** remove jquery dependence
+* **partly done** full support of json schema
+* using changeState and mutex
+* separate form design from code for form generation
+* add general using documention
+
+**Gadget for generate slapos parameter form**
+
+[gadget_erp5_page_slap_parameter_form.html](gadget_erp5_page_slap_parameter_form.html)
+
+It is the previous version of gadget used for form generation.
+It should be changed for it uses the above gadget as children
+for form generation.
+
+In this gadget the below listed specific slapos code should be saved:
+
+* gui for selection of `software type` and `serialized format output`
+* JsonDocument serialization to xml
+* JsonDocument converting to xml
+* downloading schema for user software type choice
+* text representation of form if intialJsonData is not valid for current schema
+* gui for switch to text mode custom JsonDocument input
+
+## JSON schema supported
+
+Below is the list of JSON Schema validation properties and current supported status:
+
+**array**
+
+*rendering is not supported*
+
+* `additionalItems`
+* `items`
+* `maxItems`
+* `minItems`
+* `uniqueItems`
+
+**integer** *(Number uses the same properties so if you need `number`, set your `type` explicitly)*
+
+*online input limitation should be improved*
+
+* `exclusiveMaximum`
+* `exclusiveMinimum`
+* `maximum`
+* `minimum`
+* `multipleOf`
+
+**object**
+
+* `additionalProperties`
+* `dependencies`
+* `maxProperties`
+* `minProperties`
+* `patternProperties`
+    - **fixed** values can be only `object` types
+    - add buttons for remove existed `patternProperties`
+    - can not be mixed with `properties`
+    - only regex .* in keys is supported
+* `properties`
+* `required`
+
+**string**
+
+*online input limitation should be improved*
+
+* `maxLength`
+* `minLength`
+* `pattern`
+
+