Log Message:
mitmproxy: Update net/mitmproxy to 4.0.4

pkgsrc changes:
 - Instead of maintaining patches/patch-setup.py rewrite the logic to avoid
   too strict version dependencies via SUBST.

Changes:
31 July 2018: mitmproxy 4.0.4
    * Security: Protect mitmweb against DNS rebinding. (CVE-2018-14505, @atx)
    * Reduce certificate lifetime to two years to be conformant with
      the current CA/Browser Forum Baseline Requirements. (@muffl0n)
      (https://cabforum.org/2017/03/17/ballot-193-825-day-certificate-lifetimes/)
    * Update cryptography to version 2.3.

15 June 2018: mitmproxy 4.0.3
    * Add support for IPv6 transparent mode on Windows (#3174)
    * Add Docker images for ARMv7 - Raspberry Pi (#3190)
    * Major overhaul of our release workflow - you probably won't notice it, but \ 
for us it's a big thing!
    * Fix the Python version detection on Python 3.5, we now show a more \ 
intuitive error message (#3188)
    * Fix application shutdown on Windows (#3172)
    * Fix IPv6 scope suffixes in block addon (#3164)
    * Fix options update when added (#3157)
    * Fix "Edit Flow" button in mitmweb (#3136)

15 June 2018: mitmproxy 4.0.2
    * Skipped!