[$] Change IDs for kernel patches

For all its faults, email has long provedto be an effective communication mechanism for kernel development. Similarly, Git is an effective tool forsource-code management. But there is no real connection between the two,meaning that there is no straightforward way to connect a Git commit withthe email discussions that led to its acceptance. Once a patch enters arepository, it transitions into a new form of existence and leaves its pastlife behind. Doug Anderson recently went to the ksummit-discuss list withaproposal to add Gerrit-style change IDs as a way of connecting the twolives of a kernel patch; the end result may not be quite what he was askingfor.