regarding notcurses_refresh y & x parameters

[joseluis]

I can't find any information explaining their purpose or how they should be used.

[dankamongmen]

If non-NULL, the (possibly updated) screen geometry is returned in these parameters. I've updated the inline documentation and USAGE.md to include this detail.

// Refresh the physical screen to match what was last rendered (i.e., without                              
// reflecting any changes since the last call to notcurses_render()). This is                              
// primarily useful if the screen is externally corrupted, or if an                                        
// NCKEY_RESIZE event has been read and you're not yet ready to render. The                                
// current screen geometry is returned in 'y' and 'x', if they are not NULL.                               
API int notcurses_refresh(struct notcurses* n, int* RESTRICT y, int* RESTRICT x);