sqlparser: Drop obsolete list vars from GenerateQuery
sqlparser: Introduce LIST_ARG token.
sqlparser: split row & column tuples

Row and column tuples are acquiring different semantic
meanings. This is in preparation to allow lists as
bind vars. We're only going to allow lists for column
tuples. There's not much benefit to supporting list
bind vors for row tuples.
sqlparser: Change WriteArg protocol.

Changing WriteArg to accept the full bind var including ':'.
This way, we won't have to special case list vars that start
with "::".
sqlparser: add LIST_ARG to grammar and AST.
Fixing a flaky test.
First pass at a vtworker test.
tabletserver: list bind vars support complete

You can now specify a new syntax for queries that
have an IN clause:
select * from t where id in ::list
The corresponding bind variable would be:
{"list": field_types.List([1,2,3])}

- List bind vars are only allowed for IN and NOT IN clauses.
- A bind variable can be a list if and only if
  it's referred as ::list.
- A list must contain at least one value.

For the python client, you need to supply lists using the
field_types.List class. This is because of legacy behavior
where lists were previously encoded as strings.
We should soon change this API to use native lists once we
confirm that no one will be affected by this change.
Fix package comments for vtctl.
Remove -follow flag from mysqlctl, to be replaced by mysqlctld.
Create mysqlctld service for remote mysqlctl actions.

This is intended for use internally by vttablet, in cases when it cannot
directly access the mysqld process because they are running in separate
cgroups (containers). Since vttablet and mysqld can share files, many
actions can still be done directly by vttablet. However, starting and
stopping mysqld must be done from within mysqld's cgroup, so these
actions are executed remotely by mysqlctld.
Make clone test use mysqlctld to stop and start mysqld remotely.
Merge pull request #111 from youtube/suguwork

Suguwork
Merge pull request #110 from youtube/liguo

Improve VTGate reconnection logic.
Merge pull request #112 from youtube/mysqlctl

Create mysqlctld service for remote mysqlctl actions.
Stop exporting {,Degraded}EndpointCount from VTGate - they aren't particularly meaningful.
Fixup test after removal of {,Degraded}EndpointCount debug vars.
Merge pull request #115 from plobsing/vtgate-statemon

vtgate state monitoring removal