Update s2i assembly to support multiple template html files

[jeff-phillips-18]

Related Issues and Dependencies

None

This introduces a breaking change

• [ ] Yes
• [x] No

This Pull Request implements

Allows for multiple html templates to override existing templates during s2i assembly

Description

Change the command that copies only the spawn.html file for the src templates directory to copy all html files from that directory. This allows for custom implementations of the other paths (admin, spawn-pending, etc).

[vpavlin]

lgtm