Overwriting of output files (low priority)

[ltimmerman3]

Describe the bug
If more than 100 calculations are run in the same directory (use case, vibrational calcs), the calc number is no longer appended and I believe older files are overwritten.

To Reproduce
Most efficiently would be to create a folder of dummy files labeled .out -> .out_100 and then run a sparc calculation

Expected behavior
Continued appendices corresponding to calc number

[alchem0x2A]

@ltimmerman3 I believe that's an limitation in the SPARC's C-source code as pSPARC->OutputFilename has only 2 digits (https://github.com/SPARC-X/SPARC/blob/c92931afaa4c4cbef1bbc90f7db49e2a259b8f90/src/initialization.c#L1518), but I'd argue it's not a bug (at least in the API) itself.

Personally I prefer to just pass a different directory parameter for each of these calculations, as rerunning a calculation in the same directory (with changes to .ion / .inpt files) may cause some unwanted effects when re-parsing the sparc bundle. I agree to adapt the default that keeps all output files in #42, but for this issue maybe it's better separating into different folders.