code: function list() {
      var adapters = [];
      _.each(adapterConfig, function(config, adapter) {
          var modulePath = adapterModulePath(adapter, config);
          var version, installPath, moduleName;
  
          var isBuiltin = BUILTIN_ADAPTERS.indexOf(adapter) !== -1;
          var loaded = true;
          if (isBuiltin) {
              version = juttleVersion;
              installPath = Module._resolveFilename(modulePath, module);
              moduleName = '(builtin)';
          } else {
              try {
                  var packagePath = path.join(modulePath, 'package');
                  var pkg = require(packagePath);
                  installPath = path.dirname(Module._resolveFilename(packagePath, module));
                  version = pkg.version || '(unknown)';
                  moduleName = pkg.name;
              } catch (err) {
                  installPath = '(unable to load adapter)';
                  version = '(unknown)';
                  moduleName = '(unknown)';
                  loaded = false;
              }
          }
          adapters.push({adapter: adapter, builtin: isBuiltin, module: moduleName, version: version, path: installPath, loaded: loaded});
      });
      return adapters;
  }
docs: Return a list of all configured adapters and their versions.