Ignore empty cells

Prevent cells with empty values from being exported.

This is useful for reducing file size and clutter by removing elements with no value.

Example:

Sheet name: Flame Pokemon

Name	Type1	Type2
Charmander	Fire
Charmeleon	Fire
Charizard	Fire	Flying

Default Outputs:

JSON:

{
  "Flame Pokemon" : {
    "Charmander" : {
      "Name":"Charmander",
      "Type1":"Fire",
      "Type2":null
    },
    "Charmeleon" : {
      "Name":"Charmeleon",
      "Type1":"Fire",
      "Type2":null
    },
    "Charizard" : {
      "Name":"Charizard",
      "Type1":"Fire",
      "Type2":"Flying"
    }
  }
}

XML:

<pokedex>
  <Flame_Pokemon>
    <Charmander>
      <Type1>Fire</Type1>
      <Type2></Type2>
    </Charmander>
    <Charmeleon>
      <Type1>Fire</Type1>
      <Type2></Type2>
    </Charmeleon>
    <Charizard>
      <Type1>Fire</Type1>
      <Type2>Flying</Type2>
    </Charizard>
  </Flame_Pokemon>
</pokedex>

Ignore Outputs:

JSON:

{
  "Flame Pokemon" : {
    "Charmander" : {
      "Name":"Charmander",
      "Type1":"Fire"
    },
    "Charmeleon" : {
      "Name":"Charmeleon",
      "Type1":"Fire"
    },
    "Charizard" : {
      "Name":"Charizard",
      "Type1":"Fire",
      "Type2":"Flying"
    }
  }
}

XML:

<pokedex>
  <Flame_Pokemon>
    <Charmander>
      <Type1>Fire</Type1>
    </Charmander>
    <Charmeleon>
      <Type1>Fire</Type1>
    </Charmeleon>
    <Charizard>
      <Type1>Fire</Type1>
      <Type2>Flying</Type2>
    </Charizard>
  </Flame_Pokemon>
</pokedex>