load initial session from query parameters

[fossilfriend]

these may be

• [ ] locus
• [ ] tracks
• [ ] roi

[simoncole]

Loading From Query Params

• The user can now add specific query parameters to the url that set initial conditions for the browserl
• The two options are tracks and locus, and they work similar to genomicsDB
• tracks is a comma separated list of track ids that selects from the predefined tracks data.
• locus is a locus string of the form chromosome:start-end
• The locus range results in a ROI with a flank added on either side.
• Query parameters take precedence over session storage, so if a user makes changes to the browser after navigating to a page with query parameters and then reloads, the changes will not be saved and the query parameters will be loaded instead.
• An example would be localhost:3000/?tracks=EQTL_TEST,BB_TEST_CONVERTED&locus=chr19:1070000-1090000