Make generic, removing dependency on node_runtime (#1)

* Extract error to file

* Update readme

* Extract Rpc to separate file

* Make Rpc generic over Runtime

* Editor config etc.

* rustfmt

* Remove node-runtime dependency, generic soup

* Move generic trait bounds to impl

* rustfmt

* Remove unused stuff

* Add test for balance transfer call

.editorconfig

@@ -0,0 +1,13 @@
+# EditorConfig helps developers define and maintain consistent
+# coding styles between different editors and IDEs
+# editorconfig.org
+
+root = true
+
+[*]
+end_of_line = lf
+charset = utf-8
+trim_trailing_whitespace = true
+insert_final_newline = true
+indent_style = space
+indent_size = 4