CsvDataStorage fix

[TobiasSpohn]

Description

CsvDataStorage correctly loads all lines of data in a measurement data csv file. Fix is similar to fix in #128.

Motivation and Context

When using CsvDataStorage to load data from a csv file, saved with the same interface, the first line of data is skipped.
This is due to a +2 added in the np.genfromtxt call option skip_header. Changing to a +1 correctly loads all lines of data.

How Has This Been Tested?

Jupyter Notebook calling CsvDataStorage.load_data(file_path) on a file created by the qudi-iqo-modules.pulsed_measurement_logic.save_measurement_data(storage_cls=CsvDataStorage)

Types of changes

• Bug fix
• New feature
• Breaking change (Causes existing functionality to not work as expected)

Checklist:

• My code follows the code style of this project.
• I have documented my changes in /docs/changelog.md.
• My change requires additional/updated documentation.
• I have updated the documentation accordingly.
• I have added/updated the config example for any module docstrings as necessary.
• I have checked that the change does not contain obvious errors
  (syntax, indentation, mutable default values, etc.).
• I have tested my changes using 'Load all modules' on the default dummy configuration.
• All changed Jupyter notebooks have been stripped of their output cells.

[Neverhorst]

Thanks, looks good.