* Fix up validatePageName routine
File extensions can contain numbers too.
My main motivation was to enable myself hosting `woff2` files right from
my space, like I do for `ttf` files.
Also added some tests.
* Fix up typo and add more numeric samples
* Add missing semicolons
(sorry, I'm not really js/ts programmer)
* Make linter happy
* use import_map.json instead of per-file import
* remove test_deps.ts in favor of import_map
* remove common/deps.ts in favor of import_map
* use import_map instead of server/deps.ts
* make all plug-api files usable without an import_map
* make all lib files usable without an import_map
* remove web/deps.ts in favor of import_map
* fix plug build
* remove plug-api/deps.ts in favor of lib/deps.ts
* fix server deps bundled in client deps