libsystemd-daemon-dev error when Compiling Transmission on Ubuntu 16.04+

Due to vulnerabilities in Transmission 2.92 and lower, it's important to upgrade to 2.93+, except the Ubuntu PPA has not yet been updated. Thus, one compiles!

Except, I found that compiling on Ubuntu 16.04 and above, I then could not start the service with systemd. It's possible that changing Type=notify to Type=simple in the .service file could work around the issue, but I didn't test it.

A more ideal solution is to ./configure with the --with-systemd-daemon option, except then, one encounters the error configure: error: systemd startup notification support requested, but libsystemd-daemon not found.

I think in older versions of Ubuntu, one would install libsystemd-daemon-dev, but in more recent versions, this package doesn't exist. One should install libsystemd-dev, but the transmission source for 2.93 doesn't recognize it.

The solution is to patch the source files as indicated here. Once that's done, the new --with-systemd configure option is accepted, the code compiles, and Transmission 2.93 runs happily under systemd with Type-notify!