====== 3.9.1 ======

==== Added: ====
  * Oscilloscope:
    * averaging, integration feature and examples for custom mathematic channels
    * multiple scales and zero offset for quick calibration
  * Logic Analyzer 
    * line color option, also for Patterns
    * ASCII format for: Bus, SPI, I2C, I2S; format option for I2C
  * Spectrum Analyzer
    * import and export of samples, time domain data
  * Network Analyzer:
    * spectrum measurements: Carrier, THD+N, THD, HD#
    * logarithmic scale and percentage unit, averaging option, FFT view
  * Impedance Analyzer:
    * differential setup, W1-C1P-DUT-D1N-C2-R-GND
  * Protocol tool:
    * CAN receiver filter by ID, I2C glitch filter based on frequency
    * Format option for SPI and I2C: Hexadecimal, Decimal, Binary, ASCII
  * SDK:
    * AnalogImpedance functions for network and impedance analysis
    * examples updated to be Python v3 compatible
  * Others:
    * renewed mouse wheel, drag and key operation on plots and axis
    * Locale regional option for export and import, decimal and list separator
    * device options: LED brightness; keep running, stop or shutdown on close...
    * drawing quality improvement for thicker lines
    * Notes view, further improvements and fixes...