* Moved menu titles and option names into data structures.
* Unified select menu option code
* Also unified handling of menu selection, although main and rotator menus are still handled the old way.
* Moved struct definitions to numenu.h
* Grouped functions and variables together based on usage.
* Broke up the code into more general functions instead of duplicating code
* Made stuff const and removed variables no longer used
* Use defines for menu button values
* Changed the order or things to avoid forward declarations
* Use array lookup instead of switch-case on some menu options
* Adjust menu functionification
* Cleaned up sensor rendering
This change required lots of other changes to have it compile. I had to declare all variables from NuEVI.ino used by the menu as extern in a separate header file (globals.h).
Also I moved all defines from NuEVI.ino to a config.h file. I think some of these could be moved back or even moved into menu.cpp.
I declared many variables and functions in menu.cpp as static and moved them around to avoid forward declarations. For simplicity I did some forward declarations anyway.
Some varibles only used in menu.cpp was moved from NuEVI.ino instead of having them as externals.
