Make stack pull in building phase off by default

[martindekov]

Currently --disable-stack-pull is a flag of build command which disables the pulling of templates before build phase. The default behaviour if:

configuration:
  templates:
    - name: golang-middleware

exists the template will try to be fetched every time we build.

Expected Behaviour

Rename --disable-stack-pull to --enable-stack-pull so only when flag is present the build will try to pull templates.

Current Behaviour

Tries to pull templates every time.

Possible Solution

Revert the logic of the flag.

Steps to Reproduce (for bugs)

1.Put configuration with template 2.Build 3.Build again 4.See templates are trying to be fetched every time

Context

Conversation around this was spawn in Slack.

Your Environment

• FaaS-CLI version ( Full output from: faas-cli version ): N/A
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• Are you using Docker Swarm (FaaS-swarm ) or Kubernetes (FaaS-netes)? N/A
• Operating System and version (e.g. Linux, Windows, MacOS): N/A
• Link to your project or a code example to reproduce issue: N/A

[martindekov]

When adding the feature to the build I though this should be the default case. But we can easily change it.