Specimen bar

[kaldis-berzins]

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This branch is fourth in the PR merge chain.

Specimen bar

Navbar

• Removed the navbar from App.vue. The navbar now has to be added to each view separately because it may be different for differrent views.
• The navbar is made taller and changed to accommodate the specimen bar.

  Specimen bar

• Added the specimen bar. It has the basic buttons, others are added in later branches.
• There are decently significant changes to this file in the sequence_visualizer_switcher PR, so doing a thorough review may not be necessary, but the bar should work at this point.

  Visualizers

  • Added a continue function. This exists to enable the resume button.

[gwhitney]

Starting to create a cleaned version of this to lie atop #366

[gwhitney]

Why does this PR rename saveSpecimen to saveSpecimenToBrowser? There doesn't seem to be any other sort of saving of a specimen, and so in the absence of any ambiguity, I don't see the motivation to rename. Unless someone weighs in with a justification, in the cleaned version I will leave the function called just saveSpecimen to reduce the number of changes.

[gwhitney]

Why does this PR rename saveSpecimen to saveSpecimenToBrowser?

I determined that it was because SpecimenBar had an internal function "saveSpecimen" and so the renaming was to avoid a name clash in that component. But since that was a purely internal function, I just renamed the internal one to "saveCurrent", so that the cleaned PR would touch fewer files. Closing this in favor of #367.