Add Gargantext.Utils.Selection for working with Text Selection

src/Gargantext/Utils/Selection.js

+exports._getSelection = function() { return window.getSelection() || null; };
+exports._toString = function(thing) { return thing.toString(); };

src/Gargantext/Utils/Selection.purs

+module Gargantext.Utils.Selection
+  ( class ToString, Selection, toString, getSelection ) where
+
+import Prelude ((<$>))
+import Data.Maybe (Maybe)
+import Data.Nullable (Nullable, toMaybe)
+import Effect (Effect)
+
+-- | Represents a text selection
+foreign import data Selection :: Type
+-- foreign import data Range :: Type -- Probably coming soon
+
+-- toString
+
+class ToString t
+
+instance toStringSelection :: ToString Selection
+-- instance toStringRange :: ToString Range
+
+foreign import _toString :: forall t. t -> String
+
+-- | Renders a selection or range as a string
+toString :: forall t. ToString t => t -> String
+toString = _toString
+
+-- getSelection
+
+foreign import _getSelection :: Effect (Nullable Selection)
+
+-- | Fetches the current text selection, if any
+getSelection :: Effect (Maybe Selection)
+getSelection = toMaybe <$> _getSelection
+