Remove remaining references to deprecated variable `data`

[bmurray7]

In d714b7a443991f65be1cd3574d46fa0fee58f82f, the bash variable data was deprecated and replaced with dataupper and datalower. This commit removes the remaining references to data and replaces them with references to either dataupper and datalower.

If the search for differential paths fails, the references to a deprecated variables can results in a syntax error.

if [ ! -s data/bestpath.bin.gz ]; then let data=$((2*$data)); echo "First step failed. Restarting"; sleep 2; continue; fi

./poc_no.sh: line 137: 2*: syntax error: operand expected (error token is "*")

[cr-marcstevens]

Thanks for spotting these minor bugs and for suggesting changes! Actually, the changes for lines L108 and L138 remain buggy and should use: datalower=$((2*$datalower)) If you want you can make these changes and then I'll merge the PR, otherwise I'll pick it up later this week.

[cr-marcstevens]

Thanks!