Rework resolver (#489)

* Rework IR and resolver to use nested lookup tables
* Integrate types into IR
* Make components prefer IR, slimmed down AST
* Implement `export *`
* Add `@lazy` annotation and remove `--noTreeShaking`
* Add `@start` annotation and remove magic `main`
* Related refactoring, cleanup and docs

tests/compiler/typealias.ts

@@ -1,4 +1,7 @@
-type alias = i32;
+export type alias = i32;
+// TODO: Without 'export' this yields 'ERROR TS2395: Individual declarations in merged declaration...'
+// which differs from TypeScript, but we don't have individual element and type spaces per file and this
+// just merges.
 
 export function alias(a: alias): alias {
   return a;