Force replace go_package declaration

[jekiapp]

Motivation

Since we are implementing Go module, Go always look the package declared in go_package on remote resource, even though the generated .pb files is in local. In order to make go mod look for the package in local path, we need to do go mod init for each package. It is very hard to do that since we don't know the root path of each package. Not only that, we need to put a replace statement in go.mod file neighboring server.go. (#105)

Forcing the go_package declaration under gripmock/protogen folder makes it easier for go to locate the intended package, the only thing we do is a single replace statement in go.mod file in gripmock root path.

Another reason for forcing the value update is that non Go user has no reason to put go_package in their proto other than to be used in gripmock. Even if they do, they don't know what is the right value to put in it. (#93, #99)

Changelist

• Removing declaration of go_package and replace it with our own go_package declaration.
• Add replace statement in go.mod in order to make go module looking for local resource instead of remote.
• Change dependency path for all examples