code: function getConfig(name, def) {
  
          var i, j;
  
          // Load initital config.
          if (!config) {
  
              var external;
  
              config = grunt.config.get('cog') || {options: {}};
  
              // Expand general external definitions to category specific definitions.
              if (config.options.external instanceof Array) {
                  external = config.options.external;
                  config.options.external = {lib: [], css: [], fonts: []};
                  for (i=0; i < external.length; i++) {
                      if (!db.categories[external[i]]) {
                          grunt.fail.fatal("Cannot figure out applicaple categories for external dependency: " + external[i]);
                      }
                      for(j = 0; j < db.categories[external[i]].length; j++) {
                          config.options.external[db.categories[external[i]][j]].push(external[i]);
                      }
                  }
              }
  
              // Expand also for unit tests.
              if (config.options.test && config.options.test.unit && config.options.test.unit.external instanceof Array) {
                  external = config.options.test.unit.external;
                  config.options.test.unit.lib = [];
                  config.options.test.unit.css = [];
                  for (i=0; i < external.length; i++) {
                      if (!db.categories[external[i]]) {
                          grunt.fail.fatal("Cannot figure out applicaple categories for external dependency: " + external[i]);
                          continue;
                      }
                      for(j = 0; j < db.categories[external[i]].length; j++) {
                          config.options.test.unit[db.categories[external[i]][j]].push(external[i]);
                      }
                  }
              }
          }
  
          var ret = config.options;
  
          if (!name) {
              return ret;
          }
  
          var parts = name.split('.');
          for (i=0; i < parts.length; i++) {
              if (!ret) {
                  return def;
              }
              ret = ret[parts[i]];
          }
  
          return ret || def;
      }
docs: Safe fetch of configuration variable.