define variables in oozie templates with starting and ending char

## Background
Currently, oozie variables for the template are just left bound but not right bound, eg. `$Variable` which then allows matching this even to `$Variable2`. If we make these left and right bound we lose this problem, eg. `${Variable}`

## Feature
Change oozie template variables from `$variable` to `${variable}`

## Proposed Solution [Optional]
1. Replace the strings in template
2. Use a simple function to which we provide a map of keys/values
```scala
def richFormat(string: String, replacement: Map[String, String]): String =
replacement.foldLeft(string)((res, entry) => res.replaceAll(s"\\{${entry._1}\\}", entry._2))
```