WIP: Add Tor 0.4.0.2-alpha release.

tor-versions.json

 {
+  "0.4.0.2-alpha": {
+    "tor": "tor-0.4.0.2-alpha",
+    "libevent": "release-2.1.8-stable",
+    "openssl": "OpenSSL_1_0_2q",
+    "xz": "v5.2.4",
+    "zlib": "v1.2.11",
+    "zstd": "v1.3.8",
+    "tor-android": "8eb128aa63b97e139bc845a9426b406245770096",
+    "tor_android_repo_url": "https://github.com/n8fr8/tor-android",
+    "ndk": {
+      "url": "https://dl.google.com/android/repository/android-ndk-r15c-linux-x86_64.zip",
+      "revision": "15.2.4203891",
+      "sha256": "f01788946733bf6294a36727b99366a18369904eb068a599dde8cca2c1d2ba3c"
+    }
+  },
   "0.3.5.8": {
     "tor": "tor-0.3.5.8",
     "libevent": "release-2.1.8-stable",