Update rst documentation

[thclark]

• [x] Rewrite the main documentation to remove irrelevant sections and descriptions
• [ ] Systematically update references throughout documentation from the copied reference notes to properly cross link against the bibliography
• [x] Update all references to OAS and OceanArraySystems throughout
• [ ] Go through and check equations on all functions (solving issue #35 might help)
• [x] Add octue favicon and logo
• [x] Add examples