add changes review preprocessing

Implement changes from the review of preprocessing: Issue

• Better description on the data_type argument to read_data and what the options are: addressed between lines 79 to 84.
• Remove sample_rate=16384 as hardcoded in read_data and make it user defined: addressed in line 110. Other files had to be modified to introduce this extra parameter:
  • Detector.py:changes
  • Parameters.py:changes
  • Parameters.ini:changes
  • Parameters_mock.ini:changes
  • Parameters_detector_test.ini:changes
  • Detector_test.py:changes
  • Preprocessing_test.py:changes
• Add tag argument in the read_data function as an argument the user can provide (purpose: speeding up reading public data): Line 110. Same files as in the previous bullet are changed.