Changed mu4e d key-bind in mu4e-headers-mode-map form
mu4e-headers-mark-for-trash to mu4e-headers-mark-or-move-to-trash.
Changed mu4e d key-bind in mu4e-view-mode-map form mu4e-view-mark-for-trash to mu4e-view-mark-or-move-to-trash.
Move setup files into subdirectories. Move mode directories to modes subdir.
This will make it easy to specify a recipe in melpa that maintains the directory
structure. Add interactive functions to jump to .el and README files
See #170