`inner_join` no longer reorders (#684).
less invasive handling of column names with the Name class
update NamedListAccumulator to use Name to be less invasive about column names (no automatic utf8 conversion). #722
added small strings_addresses utility used for testing that we did not invade strings (internal use only)
use Name in LazyGroupedSubsets too
give names to the addresses vector
testing no utf8 invasion #722
Update src-sql.r
Merge pull request #763 from chappers/master

Typos
merging
Merge pull request #747 from hadley/inner-join-no-reordering

`inner_join` no longer reorders (#684).
merge changes from master branch