Feature: adaptive time series analysis

[josefinez]

Add 3 approaches to adaptively identify quasi-periodic windows in I/O traces and time-frequency peak filtering for denoising. There are some open tasks from my side:

• The outputs are sets of windows with start and end points and frequency estimates, which does not match the current prediction output. This is currently handled by terminating the application in ftio_core/freq_analysis. A better strategy to process the output is required.
• It is unclear whether all approaches are supposed to be added to FTIO.
• The implementation does not include the FTIO-typical plots. In case this is of interest, I could add plots.
• I have to finalize the clean up and add some more comments.