Introduce new endpoint `/_/health` to watchdog for health status of
functions  which check for `/tmp/.lock` file

Fixes first part of #547 issue.

Signed-off-by: Vivek Singh <vivekkmr45@yahoo.in>

This enables an often-requested feature to separate stderr
from stdout within function responses. New flag combine_output is on
by default to match existing behaviour. When combine_output is set
to false it redirects stderr to the container logs rather than
combining it into the function response.

Tested with unit tests for default behaviour and new behaviour.

Signed-off-by: Alex Ellis (VMware) <alexellis2@gmail.com>

As added by previous commit with unit tests.

Signed-off-by: Alex Ellis (VMware) <alexellis2@gmail.com>

HTTP port can now be overriden through use of "port" environmental
variable.

Prefer messaging "want" over "wanted" in error messages, this is more
idiomatic Golang.

Move away from Go ARMv6 (RPi Zero) and give ARMv7 as a minimum
version for release binaries.

Signed-off-by: Alex Ellis (VMware) <alexellis2@gmail.com>

Signed-off-by: Alex Ellis <alexellis2@gmail.com>

Signed-off-by: Alex Ellis <alexellis2@gmail.com>

Signed-off-by: Alex Ellis <alexellis2@gmail.com>

Signed-off-by: Alex Ellis <alexellis2@gmail.com>

Signed-off-by: Alex Ellis <alexellis2@gmail.com>

Signed-off-by: Burton Rheutan <rheutan7@gmail.com>

Fixes 251. Set debug_write to false by default. Added log output of byte count when debug is false. Updated tests to match new default

Signed-off-by: Burton Rheutan <rheutan7@gmail.com>

Signed-off-by: Alex Ellis <alexellis2@gmail.com>

Note, not all `alexellis/github` references should be changed, there are
a number of repos which are not part of the openfaas org, this commit
excludes those.

Signed-off-by: John McCabe <john@johnmccabe.net>

Signed-off-by: Alex Ellis <alexellis2@gmail.com>

Signed-off-by: Franklin Harding <franklinharding0.0@gmail.com>

Signed-off-by: Alex Ellis <alexellis2@gmail.com>

Signed-off-by: Alex <alexellis2@gmail.com>

- Watchdog - allow new methods with and without body.
- Enforce hard-timeout via exec_timeout variable.
- Correct bug in timeouts for read/write of HTTP.
- Documentation for new verbs and hard timeout.

Signed-off-by: Alex Ellis <alexellis2@gmail.com>

* Go sync group to handle blocking on buffered-pipes

Regarding https://github.com/golang/go/issues/6785#issuecomment-275669472

Regarding https://github.com/golang/go/issues/6785#issuecomment-275669472

Don't panic on error, keep alive and return 500.

Don't panic on error, keep alive and return 500.