Agents now tee logs to local and remote.

And a few related fixes. Still need some work on using the loggers.
tabletserver: StreamExecute refactor
Using context in tm RPCs.
Fixing unit test.
tabletserver refactor: move ddl functions
tabletserver: logStats tweaks
Add search for processes by session id.
tabletserver revamp: rowcache invalidator
tabletserver: refactor transactions
Merge pull request #84 from msolo/executil-proc-stats

Add search for processes by session id.
vtctl server now tees the logs to console and remotely.
Forwarding logging for [multi]{snapshot,restore}.
Merge branch 'master' into replication
Making vtctld timeouts parameters, and default lock timeout longer.
Adding support for bytes row_splitter.
Adding worker versions of initial_sharding.py
Vitess MapReduce: Create multiple splits per shard

Currently GetMRSplits creates one split per shard. This change allows
for further splitting within a shard for better parallelism in mappers.
Splits within a shard are created by appending primary key range clauses
to the shard level query.

Changes:
Added SplitQuery RPC to VtTablet
Modified GetMRSplits to accept SQL queries instead of Table and columns
GetMRSplits forwards the query to tablet for splitting via scatterConn
Unit tests
QuerySplitter: getSplitBoundaries should panic on bad min or max
Vitess MR: Multiple splits per shard in InputFormat
Merge branch 'vtocc'