UI improvements

Collapse the activity contexts by default and show a summary of the logs.
![elmlogger7](https://cloud.githubusercontent.com/assets/2818455/5291098/1974b9ae-7b03-11e4-8688-8718e723fed4.png)

Recommend changing "http://" URLs to external resources to be "//ajax.aspnetcdn.com/...." so that in case someone has this on HTTPS it will not cause a cross-zone issue.