Here's the instructions I posted on HBT for start to finish on getting the RPi3/Jessie running start to finish:
sudo apt-get install arduino-core
git clone https://github.com/BrewPi/brewpi-tools.git ~/brewpi-tools
sudo passwd brewpi
sudo ~/brewpi-tools/updater.py --ask
(choose legacy branch both times when prompted)
*** Updating BrewPi web interface repository ***
The path '/var/www' does not seem to be a valid git repository
What path did you install the BrewPi web interface scripts to? /var/www/html
The update script can automatically check your controller firmware version and program it with the latest release on GitHub, would you like to do this now? [Y/n]:Y
Is your controller unresponsive and do you wish to try restoring your firmware? [y/N]: Y
(Choose 0.2.10 release)
sudo nano /etc/apache2/apache2.conf
Change "KeepAliveTimeout 5" to "KeepAliveTimeout 99" to deal with LCD text refresh bug.
sudo /etc/init.d/apache2 restart
Do regular setup and configuration from within web interface.