Enable functions needing native modules

This change enables build_option which allows functions to optionally add native modules by including a C/C++ build toolchain. See docs PR openfaas/docs#32 for more

Introduces cloud sub-command

Cloud sub-command is for use with openfaas-cloud and includes the ability to seal secrets using kubeseal

• #416 Add cloud sub-command for sealing secrets

See README.md for usage.

Minor fixes for build/deploy commands

• #399 Accomodate spaces in --build-arg value @rgee0
• #394 #404 Make registry auth optional for store deploy @viveksyngh @alexellis
• 6532f3c Fixes issue with double warning about insecure TLS @alexellis
• b7c6f0b Issue #410 shows registryAuth sent for local Docker images which is not required @alexellis

Make sending registry auth optional

Includes:

• Make sending registry auth optional #388

Enables flag --send-registry-auth for Docker Swarm with private repos. This isn't needed for Kubernetes so it's going behind a flag.

Misc fixes

PRs:

• Validate new function names #385

Fixes:

• Regression in 0.6.6 - panic: runtime error: slice bounds out of range #386 4e72ea6

Private registries for Docker Swarm

• Fix yaml case sensitivity around Dockerfile templates #383 @rgee0
• Add external Docker registry authentication support via arguments/YAML #372

To use a private repo with Docker Swarm then first type in docker login then when you deploy from a private repository your credentials will be passed over the wire. For this reason it is important to use HTTPS with your gateway.

Add --build-arg to faas-cli build command

• Add build-arg flag to build command #364
• Prevent duplicate function when using append flag #357 @burtonr
• Set defaultNetwork to empty value #361 @rgee0

Allow Gateway URL override in env-var: OPENFAAS_URL

Notes:

• Allows Gateway URL override in env-var: OPENFAAS_URL

I.e. you can add export OPENFAAS_URL=127.0.0.1:31112 to your .bash_rc file on Linux

Priority is explained in the README.md file

• 127.0.0.1 is the new default URL

The default host of localhost is replaced for 127.0.0.1 to avoid issues with IPv6 aliases on some Linux systems

Adds new flags to invoke and new commands

• --async flag for faas invoke #340
• --header flag for faas invoke #333
• optional username --prefix for faas new #339

Release contributors @johnmccabe @kenfdev @viveksyngh

Minor release for bug fix

faas template pull was not picking up the default repository.
Fixes brew build - #313