setting any cmdtime threshold results in panic

[bugabinga]

Setting the variable SILVER_CMDTIME_THRESHOLD to seemingly any value, results in a panic on silver init.
Values I tried:

• no value
• 1
• 10
• 500

thread 'main' panicked at 'invalid $SILVER_CMDTIME_THRESHOLD: UnknownUnit(3, 3)', src/libcore/result.rs:997:5
stack backtrace:
   0: std::sys::unix::backtrace::tracing::imp::unwind_backtrace
             at src/libstd/sys/unix/backtrace/tracing/gcc_s.rs:39
   1: std::sys_common::backtrace::_print
             at src/libstd/sys_common/backtrace.rs:70
   2: std::panicking::default_hook::{{closure}}
             at src/libstd/sys_common/backtrace.rs:58
             at src/libstd/panicking.rs:200
   3: std::panicking::default_hook
             at src/libstd/panicking.rs:215
   4: std::panicking::rust_panic_with_hook
             at src/libstd/panicking.rs:478
   5: std::panicking::continue_panic_fmt
             at src/libstd/panicking.rs:385
   6: rust_begin_unwind
             at src/libstd/panicking.rs:312
   7: core::panicking::panic_fmt
             at src/libcore/panicking.rs:85
   8: core::result::unwrap_failed
   9: silver::modules::cmdtime::segment
  10: silver::print::prompt
  11: silver::main
  12: std::rt::lang_start::{{closure}}
  13: std::panicking::try::do_call
             at src/libstd/rt.rs:49
             at src/libstd/panicking.rs:297
  14: __rust_maybe_catch_panic
             at src/libpanic_unwind/lib.rs:87
  15: std::rt::lang_start_internal
             at src/libstd/panicking.rs:276
             at src/libstd/panic.rs:388
             at src/libstd/rt.rs:48
  16: main
  17: __libc_start_main
  18: _start

The reason seems to be, that I forgot to specify the time unit (ms).
Could you document the supported time units?

My system:

  9ms  silver -V
silver
  5s 940ms  neofetch
                   -`
                  .o+`
                 `ooo/                   oli@x230
                `+oooo:                  --------
               `+oooooo:                 OS: Arch Linux x86_64
               -+oooooo+:                Host: 23255B2 ThinkPad X230
             `/:-:++oooo+:               Kernel: 5.0.10-arch1-1-ARCH
            `/++++/+++++++:              Uptime: 3 hours, 2 mins
           `/++++++++++++++:             Packages: 676 (pacman)
          `/+++ooooooooooooo/`           Shell: fish 3.0.2
         ./ooosssso++osssssso+`          WM: sway
        .oossssso-````/ossssss+`         Theme: Adwaita [GTK2/3]
       -osssssso.      :ssssssso.        Icons: Adwaita [GTK2/3]
      :osssssss/        osssso+++.       Terminal: alacritty
     /ossssssss/        +ssssooo/-       Terminal Font: monospace
   `/ossssso+/:-        -:/+osssso+-     CPU: Intel i5-3320M (4) @ 3.300G
  `+sso+:-`                 `.-/+oso:    GPU: Intel 3rd Gen Core processo
 `++:.                           `-/+/   Memory: 1626MiB / 15853MiB
 .`                                 `/

[reujab]

I documented the available suffixes: https://github.com/reujab/silver/wiki/Command-Time.