Add search box

Add search box to filter items in the current namespaces and current log
Move this line into an else statement below. No point in populating the logs twice if there is a search term.

```js
if ($scope.currentSearch) {
  $scope.logs = $log.search(namespaces, levels, $scope.currentSearch);
} else {
  $scope.logs = $log.getLogs(namespaces, levels);
}
```