gliderlabs/logspout v3.2 on GitHub

NOTE: tls is broken in v3.2

@ekkinox FIX: add build-base package install to fix missing gcc
@bobzoller reconnect log stream unless container is dead
@MattAitchison Fix locking around custom route loading
@bobzoller avoid duplicate pumps with mutex lock
@markine Use InactivityTimeout to work around a bug in docker (#204)
@MattAitchison install ca-certificates fixes #247
@MattAitchison Dockerfile: use alpine 3.5 to fix build issue from missing context pkg

@micahhausler Add Graylog GELF module
@selim Ekizoglu Exclude containers by label.
@treeder Some help for working on custom modules
@davidnortonjr Add more configuration examples to README
@davidnortonjr Filter by label (#236)
@MattAitchison first pass at tests (#218)
@grosskur syslog: Add support for SYSLOG_TIMESTAMP (#260)
@michaelshobbs add linting with go vet and golint
@andrewgaul Allow configuration of retry count via environment
@davidnortonjr Allow containers with TTY enabled using environment variable ALLOW_TTY
@michaelshobbs add golint in ci and filter /vendor/ from linting
@ebr add env.var switch to turn off backlogs
@michaelshobbs add test for max image size

@selimekizoglu Ignore empty EXCLUDE_LABEL values
@pmbauer ignore containers with unsupported log drivers
@robertjustjones Updated README to include tls
@jmreicha custom: Update README and include example build script
@josegonzalez Add a note about build.sh needing to be in the docker build directory
@treeder Much, much faster builds
@michaelshobbs set common test name prefix for -run ease
@michaelshobbs make ignoreContainerTTY more testable and add test
@michaelshobbs make retryCount testable and add test
@michaelshobbs use glide in dockerfile
@michaelshobbs use alpine + build script and add test for custom image building
@michaelshobbs attempt to preserve buffer on reconnect()
@michaelshobbs race detector for alpine is broken. disable it for now
@michaelshobbs make vet more reliable
@luketurner Don't retry sending on ECONNRESET