Release mega-20200720

Changes in mega-20200720 (since mega-20200703):

Gijs Noorlander (13):
      [Modbus RTU] Move Modbus code to .h/.cpp file to reduce size
      Convert scheduler from .ino to .cpp/.h
      [Build] Fix missing include building ESP32
      [Build] Fix build error for C018, due to removed forward declaration
      Make delay queue macro a bit more logical
      [Frontend] Only show "Submitted" message when pressing submit (#3144)
      [ESP32 ETH] Fix build issue due to recent changes
      [Arduino IDE] Fix build issue with Arduino IDE
      Fix typo in filename for P044 data struct
      [Arduino IDE] Make P076 compile again on Arduino IDE
      [Arduino IDE] Fix build issue for P035_IRTX.ino
      [Arduino IDE] Fix compile issues when selecting specific controllers
      [Syslog] Fix crash with syslog enabled on wifi (re)connect (#3147 #3072)

TD-er (2):
      Fix ADS1115 mixing input signals (#3159)
      automatically updated release notes for mega-20200720

jimmys01 (1):
      arduJSON library update

llevet (2):
      Update _P095_ILI9341.ino
      P095 Plugin: Fix bug #3047

tonhuisman (5):
      [P008] Add option to convert value to 'hex' (#3068), and updated documentation
      [TaskDisable] Bugfix for plugins without PLUGIN_EXIT implementation
      [TaskDisable] Improve readability of code after bugfix
      [TaskDisable] Remove unneeded else & return
      [P076] fix: Custom pin settings in same order as Sensor pins, improved label, improved cast