BOLD monitor with a hemodynamic model

[i-Zaak]

Describe the new feature or enhancement

Current BOLD monitor employs a HRF kernel, whereas the more widely used hemodynamic model(s) are implemented only in the BalloonModel analyzer. This would also serve as a reference implementation for the #546 and as an example for implementing integrated observer models.

Describe your proposed implementation

Refactor and adapt the analyzer code for the monitor. Verify the default values and create a demo.