Add agnes NES emulator (very slow).

Add -W <n> -H <n> width and height options to host-sdl

apps/agnes/build.zig.zon

@@ -0,0 +1,40 @@
+.{
+    // This is the default name used by packages depending on this one. For
+    // example, when a user runs `zig fetch --save <url>`, this field is used
+    // as the key in the `dependencies` table. Although the user can choose a
+    // different name, most users will stick with this provided value.
+    //
+    // It is redundant to include "zig" in this name because it is already
+    // within the Zig package namespace.
+    .name = .zigdoom,
+    .fingerprint = 0xf734231076ec3b9f,
+
+    // This is a [Semantic Version](https://semver.org/).
+    // In a future version of Zig it will be used for package deduplication.
+    .version = "0.0.1",
+
+    // This field is optional.
+    // This is currently advisory only; Zig does not yet do anything
+    // with this value.
+    //.minimum_zig_version = "0.11.0",
+
+    // This field is optional.
+    // Each dependency must either provide a `url` and `hash`, or a `path`.
+    // `zig build --fetch` can be used to fetch all dependencies of a package, recursively.
+    // Once all dependencies are fetched, `zig build` no longer requires
+    // internet connectivity.
+    .dependencies = .{
+        .zeptolibc = .{
+            .url = "git+https://github.com/ringtailsoftware/zeptolibc.git#d787abfdd597bee5616a439f12393e11fb370822",
+            .hash = "zeptolibc-0.0.1-T3flJ4M4AAAEx1K1DS-SmkmuXvJJ3JqnNHIw4Aqo0PfD",
+        },
+    },
+    .paths = .{
+        "build.zig",
+        "build.zig.zon",
+        "src",
+        // For example...
+        //"LICENSE",
+        //"README.md",
+    },
+}