Museums (#191)

* Create museums.json

New folder and blank json file for museums data

* Add files via upload

add json template file to adjust for museums

* Delete supermarkets/museums.json

deleted file saved in wrong place

* Add files via upload

Add json ready to update with museum content

* Updated JSON for museums

* Updated caveats and measure

* add csv file

* corrected period dimension to gregorian-instant

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Co-authored-by: Sazzadur Rahman <[email protected]>

museums/museums.json

@@ -20,7 +20,7 @@
     "columns": {
         "Period": {
             "type": "dimension",
-            "from_template": "gregorian-interval"
+            "from_template": "gregorian-instant"
         },
         "AREACD": {
             "type": "dimension",