Enable formatting (#188)

include/Protocol/Feature/Formatting.h

@@ -8,6 +8,19 @@ struct DocumentFormattingClientCapabilities {};
 
 using DocumentFormattingOptions = bool;
 
+struct DocumentFormattingParams {
+    /// The document to format.
+    TextDocumentIdentifier textDocument;
+};
+
+struct DocumentRangeFormattingParams {
+    /// The document to format.
+    TextDocumentIdentifier textDocument;
+
+    /// The range to format
+    Range range;
+};
+
 struct DocumentRangeFormattingClientCapabilities {};
 
 using DocumentRangeFormattingOptions = bool;