Initial LSP implementation/vscode support

newt-vscode-lsp/src/newt.d.ts

@@ -0,0 +1,5 @@
+import { Diagnostic } from "vscode-languageserver";
+
+export function LSP_updateFile(name: string, content: string): (eta: any) => any;
+export function LSP_checkFile(name: string): Diagnostic[];
+export function LSP_hoverInfo(name: string, row: number, col: number): string|null;