Add gulp support to theme deploy via ant on 7.0

• Type: Story
• Status: In Review
• Priority: Minor
• Resolution: Unresolved
• Affects Version/s: 7.0.0 Beta 8
• Fix Version/s: Master
• Component/s: Dev Tools, Dev Tools > Plugins SDK
• Labels: None
• Git Pull Request: https://github.com/brianchandotcom/liferay-plugins-ee/pull/18689

For Liferay Portal/Plugins 7.0+, we are standardizing on using gulp to generate, compile, and deploy themes. Ant still doesn't know this.
We need to make ant run new gulp utilities if a gulpfile.js file is present.