Explicit flags to control HTTP probe request timeouts for `slim` and `profile` commands: `--http-probe-req-wait`, `--http-probe-crawl-req-wait`

[kcq]

Provides an ability to adjust the currently hardcoded http request timeouts. Also need to have corresponding fields in the custom HTTP profile JSON file definitions, request_wait and crawl_request_wait.

The --http-probe-req-wait flag would adjust the timeout value globally for all custom HTTP probe requests including crawler requests.

The --http-probe-crawl-req-wait flag would adjust only the crawler request timeout value (also globally).

Adjust per-request timeouts would require the use of the JSON command file.

Note that per-request timeout adjustments are possible to implement with the --http-probe-cmd flags too, but it would require adjusting the parsing logic for the value, so there's a place for the custom request timeouts. The probe command flag value is already busy as-is though and adding custom request timeouts will make it even messier and harder to use.