Oxfordshire: Implement usability recommendations

- [x] Change the label on the home page search box from **Report a street or road problem** to **Find and report road or street problems**.
- [x] Use next zoom level (in) on maps as default, so street names are visible.
- [x] Use full width map with overlay, as in attached mock-ups (report1.jpg and report2.jpg)
- [x] Update help text for plotting a new problem as per attachment (report1.jpg) – including key to the yellow pins
- [x] Move help/guidance text into side window, moving the form above the fold, as per attachment (report2.jpg)

###### report1.jpg

![report1](https://f.cloud.github.com/assets/22996/923158/85e41f30-ff3f-11e2-81f5-f1ab7b031ce4.jpg)

###### report2.jpg

![report2](https://f.cloud.github.com/assets/22996/923160/91b3bd34-ff3f-11e2-9195-846f5a482363.jpg)