Adds `use_framing` config to all output plugins, and `Encode` and
`UsesFraming` methods to the OutputRunner. If use_framing is true,
then OutputRunner.Encode will prepend the framing, and UsesFraming
will return true. If false, OutputRunner.Encode will return the output
from Encoder.Encode unadorned, and UsesFraming will return false.

All outputs currently using encoders for serialization have been
updated to use the new spelling.
Merge pull request #931 from mozilla-services/outputrunner-encodes

OutputRunner encoding
First pass at adding array support to ESJsonEncoder.
Cleanup the unit tests on Windows
Fix up the Unix unit test
Pull in the recent lua_sandbox changes
Merge pull request #935 from mozilla-services/window_cleanup

Cleanup the unit tests on Windows
All field types now support arrays in ESJsonEncoder.
Fix up line endings on one more test file
Issue #504 Always use UTC times in the ElasticSearch bulk header API
Merge pull request #938 from mozilla-services/issue_504

Issue #504 Always use UTC times in the ElasticSearch bulk header API
Change FileOutput and TcpOutput to default to use_framing = true if a
ProtobufEncoder is being used, use_framing = false if any other
decoder is being used. The setting can still be overridden by explicitly
setting it in the config.
Remove outdated `prefix_ts` documentation, fix bug in use_framing
config processing.
Fix runner interface typo.
Add a test to verify that the OutputRunner actually adds framing when
it has been told to do so.
Merge pull request #940 from mozilla-services/tcp-file-framing-default

Change FileOutput and TcpOutput to default to use_framing = true if a
Removed reflection from writeRawArrayField.
Added HttpOutput.
Tell travis to use Go 1.3.
Fix test failures happening on i386.