Update release notes for 1.15
Update release notes for 1.15
Merge branch 'wm-notes-1.15.0' of https://github.com/rethinkdb/rethinkdb into wm-notes-1.15.0

Conflicts:
	NOTES.md
Add missing PR
Add a few newly-closed issues
Fix version number
Fix errant edit
Updates based on comments
More updates, two new issues
Change release name
Change 'update' to 'replace'
Clarify "upgrading" tables
Don't permit object-like operations on ptypes
Thread checks in where it makes sense.
Test merge arguments too
Insert checks for merge arguments
Test path arguments
Worked around cpplint recursion bugs in a bunch of geo code.

It all mysteriously was scoped_keyvalue_pair_t && that tripped IsRValueType recursion.
initial commit for #3084 polyglot/sindex/truncation.rb failing with "can't convert Fixnum into String"
initial commit for #3081 macos pkg permissions