Add flag 'log-color' which preserves colors of log when stdout is redirected to a file.
This is my first lighthouse PR, please let me know if I'm not following contribution guidelines, I welcome meta-feeback (feedback on git commit messages, git branch naming, and the contents of the description of this PR.)
## Issue Addressed
Solves https://github.com/sigp/lighthouse/issues/3527
## Proposed Changes
Adding a flag which enables log color preserving when stdout is redirected to a file.
### Usage
Below I demonstrate current behaviour (without using the new flag) and the new behaviur (when using new flag).
In the screenshot below, I have to panes, one on top running `lighthouse` which redirects to file `~/Desktop/test.log` and one pane in the bottom which runs `tail -f ~/Desktop/test.log`.
#### Current behaviour
```sh
lighthouse --network prater vc |& tee -a ~/Desktop/test.log
```
**Result is no colors**
<img width="1624" alt="current" src="https://user-images.githubusercontent.com/864410/188258226-bfcf8271-4c9e-474c-848e-ac92a60df25c.png">
#### New behaviour
```sh
lighthouse --network prater vc --log-color |& tee -a ~/Desktop/test.log
```
**Result is colors** 🔴🟢🔵🟡
<img width="1624" alt="new" src="https://user-images.githubusercontent.com/864410/188258223-7d9ecf09-92c8-4cba-8f24-bd4d88fc0353.png">
## Additional Info
I chose American spelling of "color" instead of Brittish "colour' since that was aligned with `slog`'s API - method`force_color()`, let me know if you prefer spelling "colour" instead. I also chose to let it be an arg not taking any argument, just like `logfile-compress` flag, rather than having to write `--log-color true`.
419c53bf24
