Add support for time

[prsabahrami]

I have implemented a basic implementation for adding time to shell but not sure about the behaviour on Windows. @certik Can you please check this on Windows?

[codecov]

Codecov Report

Attention: Patch coverage is 4.44444% with 43 lines in your changes missing coverage. Please review.

Project coverage is 63.22%. Comparing base (175858c) to head (5e1afcb).
Report is 1 commits behind head on main.

Files with missing lines	Patch %	Lines
crates/shell/src/commands/time.rs	0.00%	43 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #254      +/-   ##
==========================================
- Coverage   63.86%   63.22%   -0.64%     
==========================================
  Files          32       33       +1     
  Lines        3664     3712      +48     
==========================================
+ Hits         2340     2347       +7     
- Misses       1324     1365      +41     

Files with missing lines	Coverage Δ
crates/shell/src/commands/mod.rs	45.20% <100.00%> (+1.54%)	⬆️
crates/shell/src/commands/time.rs	0.00% <0.00%> (ø)

... and 3 files with indirect coverage changes

[certik]

I think this looks good as the initial implementation. Thanks!

[certik]

I tested it on Windows, I think it works!

~/repos/shell(main)$ time cargo build -r
   Compiling tests v0.1.0 (C:\Users\ondrejcertik\repos\shell\crates\tests)
    Finished `release` profile [optimized] target(s) in 1.52s

real    1.758s
user    0.000s
sys     0.000s
cpu     0.0%
~/repos/shell(main)$ time cargo build -r
    Finished `release` profile [optimized] target(s) in 1.01s

real    1.154s
user    0.000s
sys     0.016s
cpu     1.4%
~/repos/shell(main)$ time cargo build -r
    Finished `release` profile [optimized] target(s) in 0.85s

real    1.005s
user    0.000s
sys     0.016s
cpu     1.6%
~/repos/shell(main)$ time cargo build -r
    Finished `release` profile [optimized] target(s) in 0.93s

real    1.098s
user    0.000s
sys     0.016s
cpu     1.4%

Great job. Thanks for fixing it.