[docs] Put DeveloperPolicy under "Development Process Documentation"

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178421 91177308-0d34-0410-b5e6-96231b3b80d8
[docs] The GEP FAQ is not "design and overview"

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178422 91177308-0d34-0410-b5e6-96231b3b80d8
[docs] Pull IRC and Mailing Lists under a new "Community" heading.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178423 91177308-0d34-0410-b5e6-96231b3b80d8
[docs] Reorganize mailing lists.

Order them roughly by "which one should a newbie join first".

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178424 91177308-0d34-0410-b5e6-96231b3b80d8
[docs] Annotate mailing lists with their "name".

Nobody says "the developer's list" or "commits archive"; they always say
"llvmdev" or "llvm-commits". It makes sense for our documentation to
at least make that association explicitly.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@178425 91177308-0d34-0410-b5e6-96231b3b80d8