fix: resolve issue saving pitch tiers

[timmahrt]

After not running ProMo for a long time, I found that it no longer ran properly. Running tests showed the error:

Error: Early end of text detected while looking for a real number (line 165).
"number" not read.
PitchTier not read.
Data not read from text file “/Users/tmahrt/Dropbox/workspace/promo/examples/files/pitchTiers/mary1_mary1_stylized_f0_morph_0.333.PitchTier”.

I traced the issue to a behavior change with NumPy and how it handles floats. I modified praatio to normalize numbers when adding data to data files (like PitchTiers).

This PR:

• pins the version of praatio to one that contains the bugfix
• updates relevant documentation and example files
• replaces setup.py with pyproject.toml

[timmahrt]

WavQueryObj was deleted at some point. This is the current way to use the library to get duration.