Added form handling

Added functionality so that a user can submit a message and then see it
displayed in the browser windows. Go HTML Templates were used.
Revert "Added Google Login support to greet specific user"

This reverts commit 0534fa8d7f0d438452654aaf8015760e02cd6733.
Merge branch 'web-form'

Conflicts:
	hello/hello.go
Resolve conflicts

The web-form branch does not need the old handler that sent the
response "Hello World !!!" for every request. That functionality was
deleted to resolve the conflicts.