[DISCUSS] A more inclusive community - Rename master branch to trunk

[Jonathan Eagles <je...@gmail.com>]

A step towards inclusion has been made.

I have filed https://issues.apache.org/jira/browse/TEZ-4217 as an umbrella
jira to contain sub-tasks of work that will move the Tez community
towards inclusivity. As a first pass, I have requested the removal of
whitelist/blacklist, master/slave terminology, and added a task towards
enforcing inclusive language policies. I expect that umbrella to remain
open to reflect that the work a journey and is never done.

To that end, I propose renaming the master branch to trunk. The process for
this change is 1) creating a new branch trunk based on the master branch,
2) modify build configuration (including default branch in YETUS), 3)
update and publish documentation/website, and 4) notify INFRA to switch.
master branch will be EOL'd, but will remain in place to allow external
build systems to continue using this until migration to trunk is complete.

Regards,
Jon Eagles
Tez PMC Chair