Optimized build for IPQ40xx devices

The release is done, please check it out. I've documented one of the stronges features of this v1.15.oc version, which you can read here:

Also, I've implemented 2 important features:

  1. The hotfixes, which is a backup-compatible file to fix small annoyances that I forgot to implement in the main image, or that failed my tests once the packages and images were ready.
  2. A better error and crash reporting mechanics, when the device stores their dying breath in a reserved section of RAM that it's available once the device reboots. Along with it, an automatic script to recollect the data from RAM.

If your device crashes for any reason, or you think you have a problem, contact me directly on GitHub issues with a copy of all the files in /sys/fs/pstore and /rom/bootfs/pstore. If your logs contains any private, sensible or otherwise important information, send them to my email, but always open a GitHub issue.