flogo Build failing on freshly created activity using cli

[pradyuz3rocool]

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[] enhancement request
[] feature request
[] support request
[] general question

Current behavior (how does the issue manifest):
The flogo build is giving the following issue

[error] Encountered error while installing the 'https://github.com/pradyuz3rocool/flogo-workspace/activity/dhtxx' to the engine:
2018-12-05T10:18:00.268Z - error: # flogo-web/vendor/github.com/pradyuz3rocool/flogo-workspace/activity/dhtxx
vendor/github.com/pradyuz3rocool/flogo-workspace/activity/dhtxx/activity_metadata.go:36:20: undefined: NewActivity
FATAL: command "build" failed: exit status 2

Expected behavior:

Minimal steps to reproduce the problem (not required if feature enhancement):

What is the motivation / use case for changing the behavior?

Please tell us about your environment (Operating system, docker version, browser & verison if webui, etc):

OSX Mojave, Docker engine 18.09.0, chrome, logo v0.5.6
Flogo version (CLI & contrib/lib. If unknown, leave empty or state unknown): 0.X.X

Additional information you deem important (e.g. issue happens only occasionally):

[fcastill]

Hi @pradyuz3rocool, based on the error message I'm assuming this is an issue with the Web UI. Would you please provide more information on how to reproduce this issue? What steps are you following? What URL are you using when installing the activity?