add clustered markers and photo tooltips

[courtneysimonse]

These edits do a few things:

1. Change the marker to circleMarker to make customizing the marker easier.
2. Allow multiple markers to be added for each story map section, with support for adding images to the tooltip.
3. Add marker clustering using Leaflet.markercluster (https://github.com/Leaflet/Leaflet.markercluster).

[atlefren]

Looks fine to me. I'm not maintaining this repo anymore, let me know if you want administrator rights

[courtneysimonse]

Sure, I have some ideas for using it in a couple projects. Courtney

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On Mon, Jul 15, 2019, 7:10 AM Atle Frenvik Sveen ***@***.***> wrote: Looks fine to me. I'm not maintaining this repo anymore, let me know if you want administrator rights — You are receiving this because you authored the thread. Reply to this email directly, view it on GitHub <#4?email_source=notifications&email_token=AG5FF5MFXBWWJJR5QE2OW5TP7SAPBA5CNFSM4IC7OB3KYY3PNVWWK3TUL52HS4DFVREXG43VMVBW63LNMVXHJKTDN5WW2ZLOORPWSZGODZ52CKI#issuecomment-511418665>, or mute the thread <https://github.com/notifications/unsubscribe-auth/AG5FF5KDQNC3QFLK53XDZHDP7SAPBANCNFSM4IC7OB3A> .