The key is: 'hyp_page_search_query'
Upon VS initialization, if available, the query is retrieved and feed to VS.

- Using '-' instead of '_'
- sidebar does not resize when search bar grows

common.scss contains our overrides for it.

- Original search highlighting modified the text field
- It was a permanent change, it is no longer that way.
- Annotation directive using a mode attribute, to differentiate between viewer and search display
- We show highlighted text only for search results
- It can be used for other differences

Introduce show_search boolean in class Hypothesis

- No longer part of the viewer
- Has its own controller: Search
- Own page: page_search.html