* refactor: use UNMOUNT instead of DISMOUNT in code
This change updates the term DISMOUNT in constants to UNMOUNT.
Other occurrences (e.g. variable names) are left alone for now.
* refactor(ui): use unmount instead of dismount
This change updates the GUI text and replaces dismount with unmount.
* docs: update term dismount -> unmount
* refactor(cmdline): add unmount
This change adds an argument 'unmount' for command line usage, while
trying to deprecate the old disnount argument.
The current dismount argument/flag will still work to not introduce
a breaking change.
* docs: mention that /dismount is deprecated
This change fixes the shorthand version of the argument /unmount
It also adds back the info for /dismount and that it is deprecated.
