Support -F style trailing characters

[jwfearn]

[I can't find how to do this in docs, if it's possible then maybe add -F as the supported short option.]

Support for trailing characters to identify directories, executables, links, etc. Like the -F option to ls. From man ls:

     -F      Display a slash (‘/’) immediately after each pathname that is a directory, 
             an asterisk (‘*’) after each that is executable, an at sign (‘@’) after each 
             symbolic link, an equals sign (‘=’) after each socket, a percent sign (‘%’) 
             after each whiteout, and a vertical bar (‘|’) after each that is a FIFO.

[solidiquis]

Great suggestion! Can do

[jwfearn]

Suggested long option for -F: --classify. From another man ls:

  -F, --classify             append indicator (one of */=>@|) to entries

[retrobit]

Also, tree supports this "...as per ls -F": https://linux.die.net/man/1/tree