minor, update "make clean".
update README to add some dev notes.

this allow running mbackup.exe without showing the cmd.exe window.

/RU SYSTEM run mbackup will fail. probably because expand special
folder fail for SYSTEM user.

install local-list.txt and locl-exclude.txt by default, but don't
overwrite if already exists on target system.

file. Now all options except --versin and -i are supported in config
file

specify known hosts file explicitly, so wrong home doesn't matter.

- allow msi major upgrade
- add desktop and start menu shortcut for mbackup.exe file
- set HOME env variable when running rsync.exe.
  ssh.exe wants to access HOME dir.
  but this change seems not working in win 10 VM.
- add Version info in mbackup.fsproj
  - mbackup.exe supports --version option.
    - when build msi file, include version in filename
    - use printf %A to print exception detail.

fail fast if ssh key doesn't exist. don't run rsync.

formatted code using vscode format document command

mbackup.list file; create dir should use windows format dir string.

- renmaed mbackup-for-windows.fsproj to mbackup.fsproj
  this file name is the project name. now exe is named mbackup.exe
- use framework dependent release.
- include rsync-mingw in one msi
- use installed rsync and ssh path in Program.fs

- introduced wix, make
- rsync-mingw64.msi works
- I decide to include rsync inside mbackup.msi, and install it in
  the same app dir. So this working rsync-mingw64.msi config will
  be removed in next commit.

cli option > env var > config file

now target can be specified in config file.
renamed some function to use camelCase.

removed the old logger workaround when no object is used in fmt.

logger functions now support variable number of arguments.

now rsync should work if ssh key is present.

added short option support;
use real rsync command in Process.Start();

added unit test sub project.

fixed local.exclude typo

still missing many pieces and missing windows specific handling.