FCM/GCM: template parameters are not correctly replaced

I'm using the Notification Hub client lib 1.0.9

I am registering a template like this:

```
{
"notification" : {
"title" : "$(sender)",
"body" : "$(message)"
}
}
```

When I send my templates message I populate the params dictionary with the keys `sender` and `message` and they will be replaced as expected and result in the following output:

```
{com.google.firebase.messaging.RemoteMessage$Notification@305d335}
Body: "hallo2"
Title: "Bulk message from backend"

```
Notice how body and title are correctly set.

Then I change my template to include additional text like below:

```
{
"notification" : {
"title" : "$(sender)",
"body" : "Some other text. $(message)"
}
}

```
and the result is:

```
{com.google.firebase.messaging.RemoteMessage$Notification@4c9d296}
Body: "Some other text. $(message)"
Title: "Bulk message from backend"

```
The `message` placeholder is not being replaced anymore. This is for FCM/GCM only and work fine for iOS templates.