Proto/Swagger HTTP JSON to RPC mapping

## Problem
The current HTTP JSON to RPC mapping does not seem to generate proper string replacement logic, so the HTTP request will always result in a `404`.

### Example

The following would yield a `404`

```golang
grafeasCfg := &grafeasAPI.Configuration{
BasePath: "http://localhost:8080",
DefaultHeader: make(map[string]string),
UserAgent: "Swagger-Codegen/0.1.0/go",
}
grafeasClient := grafeasAPI.NewAPIClient(grafeasCfg)
projectID := "projects/myproject"
notesResp, _, err := grafeasClient.GrafeasV1Beta1Api.ListNotes(context.Background(), projectID, nil)
if err != nil {
log.Fatal(err)
} else {
log.Print(notesResp.Notes)
}
```

While a `curl` against that same project would yield a `200`

```shell
$ curl http://localhost:8080/v1beta1/projects/myproject/notes
{"notes":[],"nextPageToken":""}
```

### Proto generated client

The following shows the broken string replacement logic

```golang
// create path and map variables
localVarPath := a.client.cfg.BasePath + "/v1beta1/{parent=projects/*}/notes"
localVarPath = strings.Replace(localVarPath, "{"+"parent"+"}", fmt.Sprintf("%v", parent), -1)
```

[Reference to code](https://github.com/grafeas/client-go/blob/39fa98b49d38de3942716c0f58f3505012415470/0.1.0/api_grafeas_v1_beta1.go#L1067-#L1068)

Derived from:
https://github.com/grafeas/grafeas/blob/6a8d995912a9f10f732e8ffcffbae8830507ed17/proto/v1beta1/grafeas.proto#L121

### Simulated

```golang
parent := "projects/myproject"
localVarPath := "http://localhost:8080" + "/v1beta1/{parent=projects/*}/notes"
fmt.Println("[CURRENT] BEFORE REPLACEMENT:", localVarPath)
localVarPath = strings.Replace(localVarPath, "{"+"parent"+"}", fmt.Sprintf("%v", parent), -1)
fmt.Println("[CURRENT] AFTER REPLACEMENT :", localVarPath)
localVarPath = "http://localhost:8080" + "/v1beta1/{parent}/notes"
fmt.Println("[PROPOSED] BEFORE REPLACEMENT:", localVarPath)
localVarPath = strings.Replace(localVarPath, "{"+"parent"+"}", fmt.Sprintf("%v", parent), -1)
fmt.Println("[PROPOSED] AFTER REPLACEMENT :", localVarPath)
// [CURRENT] BEFORE REPLACEMENT: http://localhost:8080/v1beta1/{parent=projects/*}/notes
// [CURRENT] AFTER REPLACEMENT : http://localhost:8080/v1beta1/{parent=projects/*}/notes
// [PROPOSED] BEFORE REPLACEMENT: http://localhost:8080/v1beta1/{parent}/notes
// [PROPOSED] AFTER REPLACEMENT : http://localhost:8080/v1beta1/projects/myproject/notes
```

## Solution

I haven't had time to test yet but changing

```proto
rpc ListNotes(ListNotesRequest) returns (ListNotesResponse) {
option (google.api.http) = {
get: "/v1beta1/{parent=projects/*}/notes"
};
};
```

to

```proto
rpc ListNotes(ListNotesRequest) returns (ListNotesResponse) {
option (google.api.http) = {
get: "/v1beta1/{parent}/notes"
};
};
```

should work