jsonschema: add CLOUDCOVER, PRECIP:24HR fields (#118)

Author: mackenzie-grimes-noaa

python/idsse_common/idsse/common/schema/field.json

@@ -7,6 +7,8 @@
           "AppTemp",
           "CEILING",
           "Ceiling",
+          "CLOUDCOVER",
+          "CloudCover",
           "CREF",
           "DEWPOINT",
           "DewPoint",
@@ -27,6 +29,8 @@
           "Precip:1HR",
           "PRECIP:6HR",
           "Precip:6HR",
+          "PRECIP:24HR",
+          "Precip:24HR",
           "PROBTHDR:1HR",
           "ProbThdr:1HR",
           "PROBTHDR:3HR",
@@ -54,6 +58,7 @@
           "VISIBILITY",
           "Visibility",
           "WAVEHEIGHT",
+          "WaveHeight",
           "WBGT",
           "WET_BULB",
           "WINDDIR",