Handle subscription of messages in the webapp.

Messages larger than a threshold are split and reassembled due to the
size limit in webrtc. Threshold may have to be adjusted somewhere between
64KiB and 256KiB.

This also includes a basic handler for a ping message and a more
advanced image handler.

Change-Id: If66acfb1bb84e9d3ff686994a94b1480cb70b2aa
diff --git a/aos/network/www/BUILD b/aos/network/www/BUILD
index 5faae12..76e8ef4 100644
--- a/aos/network/www/BUILD
+++ b/aos/network/www/BUILD
@@ -5,27 +5,42 @@
     name = "files",
     srcs = glob([
         "**/*.html",
+        "**/*.css",
     ]),
     visibility=["//visibility:public"],
 )
 
 ts_library(
     name = "proxy",
-    srcs = glob([
-        "*.ts",
-    ]),
+    srcs = [
+        "config_handler.ts",
+        "proxy.ts",
+    ],
     deps = [
         "//aos/network:web_proxy_ts_fbs",
     ],
+    visibility=["//visibility:public"],
+)
+
+ts_library(
+    name = "main",
+    srcs = [
+        "main.ts",
+        "ping_handler.ts",
+    ],
+    deps = [
+        ":proxy",
+        "//aos/events:ping_ts_fbs",
+    ],
 )
 
 rollup_bundle(
-    name = "proxy_bundle",
+    name = "main_bundle",
     entry_point = "aos/network/www/main",
     deps = [
-        "proxy",
+        "main",
     ],
-    visibility=["//visibility:public"],
+    visibility=["//aos:__subpackages__"],
 )
 
 genrule(
@@ -37,5 +52,5 @@
         "flatbuffers.js",
     ],
     cmd = "cp $(location @com_github_google_flatbuffers//:flatjs) $@",
-    visibility=["//visibility:public"],
+    visibility=["//aos:__subpackages__"],
 )