Feature request: configurable client data collection

[marcg1]

Please consider making client data collection configurable: enabled or disabled. For certain PII-sensitive use cases, MD5 obfuscation may not be adequate. If a user's MAC address or name is known, for example, the obfuscated version could be calculated by an attacker and then tracked in the obfuscated data.

unpoller is a great contribution to the community ... thanks!