add warning for missing recipe file

[twc7c]

lt.filter_logs() returns an error if searching for a recipe that does not exist (e.g. when you are pointed to the AJA_metals files but looking for a recipe from the AJA_dielectrics tool.

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IndexError Traceback (most recent call last)
in ()
6
7 #Grab a list of the column headings (aka keys) from the first file
----> 8 keys_all = list(rlogs.values())[0]['data'].keys()
9 print(keys_all)

IndexError: list index out of range