Handle frequency data from old auto_rx versions correctly.

Old auto_rx versions (1.5.10) seem to be providing frequency information as a string in some cases (possibly with the 'experimental decoders' turned off?) Either way, it was resulting in a heap of problems as we weren't coercing the frequency value to float before calling toFixed(4) on it.

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v2.7.5

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tile server update

Update sondehub.js - Use preferred tile.openstreetmap.org URL

See https://github.com/openstreetmap/operations/issues/737

v2.7.3

Bump min required zooming so that our mqtt servers survive.

Full Changelog: v2.7.2...v2.7.3

(Hopefully) fix launch site predictions being generated for the wrong dates

Full Changelog: v2.7.1...v2.7.2

Moving to github releases

v2.7.1

fix bug where up location permission tries to turn on chase car!