index.js: Implement embark-mythx plugin.

The embark-mythx plugin uses Mythos (https://github.com/cleanunicorn/mythos)
to connect to MythX cloud service.

Create your own MythX API account and add

"plugins": {
    "@cryptomental/embark-mythx":
        {
          "mythxEthAddress": "YourMythXEthAddress",
          "mythxPassword":   "YourMythXEthPassword"
        }
  }

Author: cryptomental

index.js

@@ -0,0 +1,36 @@
+const shelljs = require("shelljs");
+
+function isMythosInstalled() {
+  return shelljs.test("-f", "node_modules/.bin/mythos");
+}
+
+function executeMythos(contractFilePath, contractName, mythxEthAddress, mythxPassword, logger) {
+  shelljs.exec(`node_modules/.bin/mythos analyze ${contractFilePath} ${contractName} --mythxEthAddress=${mythxEthAddress} --mythxPassword=${mythxPassword}`,
+    { silent: true }, function (code, stdout, stderr) {
+      if (stderr) {
+        logger.info(stderr);
+      }
+      logger.info(stdout);
+    });
+}
+
+async function run(embark, compilationResult) {
+  if (!isMythosInstalled()) {
+    embark.logger.warn("Mythos not found! Plugin dependencies were not installed correctly.");
+    return;
+  }
+
+  Object.keys(compilationResult.contracts).map((contractFilePath) => {
+    Object.keys(compilationResult.contracts[contractFilePath]).map((contractName) => {
+      embark.logger.info(`Requesting analysis of ${contractName} from ${contractFilePath}`);
+      executeMythos(contractFilePath, contractName, embark.pluginConfig.mythxEthAddress, embark.pluginConfig.mythxPassword, embark.logger);
+    });
+  });
+
+}
+
+function register(embark) {
+  embark.events.on("contracts:compiled:solc", run.bind(null, embark));
+}
+
+module.exports = register;