UI state deep linking

[bcardarella]

When I am changing the UI state the changes should be represented in the URL. For example, if a boat is selected and the time scrubber range is changed the url should now reflect this change so that the URL can be shared with others and the app launches showing that exact state.

We can rely on query params to do this and setting up / reading the data in handle_params or where ever is appropriate.

We want to represent the following UI elements in the URL:

• when first launching the app the LV should push_patch to the current date if there is no date in the URL
• when changing the date the date should be represented in the URL as an ISO 8601 value YYYY-MM-DD: https://en.wikipedia.org/wiki/ISO_8601 (# 1)
• no boats should be pre-selected (# 2)
• boats selected - when selecting boats to visualize this collection should be represented in the URL (# 2)
• the time range scrubber start & stop (# 3) should be represented as fractional ISO 8601 time HH::MM::SS
• the current playback position (# 4) should be represented in the URL as fractional ISO 8601 time HH::MM::SS