Refactoring of formatting for 0 in tablegenerator
Refactoring of formatting for 0 in tablegenerator

With the switch to Decimal, we can use more of the same code that also
handles other numbers for handling 0.

ultimate-pa/benchexec,sosy-lab/benchexec,sosy-lab/benchexec,dbeyer/benchexec,dbeyer/benchexec,ultimate-pa/benchexec,sosy-lab/benchexec,ultimate-pa/benchexec,ultimate-pa/benchexec,ultimate-pa/benchexec,ultimate-pa/benchexec,sosy-lab/benchexec,sosy-lab/benchexec,dbeyer/benchexec,sosy-lab/benchexec,dbeyer/benchexec