Add Dockerfile to build Sync Gateway from source (#3606)
Add Dockerfile to build Sync Gateway from source (#3606)

* Add dockerfile for building SG from source

* Remove (presumably) unused Makefile to balance out the addition of the added Dockerfile

* Revert "Remove (presumably) unused Makefile to balance out the addition of the added Dockerfile"

This reverts commit 657a1492a117040f8c89b7a5cdcb0ce19bc13d80.

* Integrate @bbrks PR feedback (one tweak, use —from=builder instead of —from=0)

couchbaselabs/sync_gateway,ceejatec/sync_gateway,couchbaselabs/sync_gateway,couchbaselabs/sync_gateway,couchbaselabs/sync_gateway,ceejatec/sync_gateway,ceejatec/sync_gateway,ceejatec/sync_gateway