Fix Self's action type (#74)

Resolves #71

Author: spicydonuts

src/React/Basic.purs

@@ -181,7 +181,7 @@ data StateUpdate props state action
 type Self props state action =
   { props     :: props
   , state     :: state
-  , instance_ :: ReactComponentInstance
+  , instance_ :: ReactComponentInstance props state action
   }
 
 -- | Dispatch an `action` into the component to be handled by `update`.
@@ -408,12 +408,12 @@ foreign import displayNameFromSelf
 -- | ```
 -- |
 -- | __*See also:* `element`, `toReactComponent`__
-data ReactComponent props
+foreign import data ReactComponent :: Type -> Type
 
 -- | An opaque representation of a React component's instance (`this` in the JavaScript
 -- | React paradigm). It exists as an escape hatch to unsafe behavior. Use it with
 -- | caution.
-data ReactComponentInstance
+foreign import data ReactComponentInstance :: Type -> Type -> Type -> Type
 
 -- | Convert a React-Basic `ComponentSpec` to a JavaScript-friendly React component.
 -- | This function should only be used for JS interop and not normal React-Basic usage.

src/React/Basic/DOM.purs

@@ -93,15 +93,15 @@ foreign import unmountComponentAtNode_ :: EffectFn1 Element Boolean
 -- | `React.Basic.DOM.Components.Ref` where possible__
 -- |
 -- | __*Note:* Relies on `ReactDOM.findDOMNode`__
-findDOMNode :: ReactComponentInstance -> Effect (Either Error Node)
+findDOMNode :: forall props state action. ReactComponentInstance props state action -> Effect (Either Error Node)
 findDOMNode instance_ = try do
   node <- runEffectFn1 findDOMNode_ instance_
   case toMaybe node of
     Nothing -> throw "Node not found."
     Just n  -> pure n
 
 -- | Warning: Relies on `ReactDOM.findDOMNode` which may throw exceptions
-foreign import findDOMNode_ :: EffectFn1 ReactComponentInstance (Nullable Node)
+foreign import findDOMNode_ :: forall props state action. EffectFn1 (ReactComponentInstance props state action) (Nullable Node)
 
 -- | Divert a render tree into a separate DOM node. The node's
 -- | content will be overwritten and managed by React, similar