Add --ftime-trace to dmd

[dkorpel]

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Reboot of https://github.com/dlang/dmd/pull/13965

This feature has been in LDC for a while now with success, and inclusion into dmd has been pre-approved a long time ago by Walter, but the PR has stalled since then. There's improvements possible with choosing better zones and refactoring the code, but for now I focused on making it closely match LDC's current implementation.

For this PR, I still need to include the timetrace2txt tool, and test it a bit better.

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Testing this PR locally

If you don't have a local development environment setup, you can use Digger to test this PR:

dub run digger -- build "master + dmd#16363"

[dkorpel]

I've tested what the overhead is of normal compilation without -ftime-trace on a copy of Phobos.

hyperfine "dmds0 -i -c mystd/package.d" "dmds1 -i -c mystd/package.d"
Benchmark 1: dmds0 -i -c mystd/package.d
  Time (mean ± σ):      1.540 s ±  0.019 s    [User: 1.213 s, System: 0.316 s]
  Range (min … max):    1.520 s …  1.576 s    10 runs
 
Benchmark 2: dmds1 -i -c mystd/package.d
  Time (mean ± σ):      1.553 s ±  0.011 s    [User: 1.206 s, System: 0.335 s]
  Range (min … max):    1.538 s …  1.572 s    10 runs
 
Summary
  dmds0 -i -c mystd/package.d ran
    1.01 ± 0.01 times faster than dmds1 -i -c mystd/package.d

(dmds0 = master branch, dmds1 = ftime-trace branch)

So ~1% overhead, which is worth it when you see how much build time this feature can save.

[RazvanN7]

@ibuclaw @JohanEngelen anything else blocking this PR?

[JohanEngelen]

@ibuclaw @JohanEngelen anything else blocking this PR?

I have not reviewed in detail this time, but I trust it is OK. A great addition to the frontend!