Overwrite the scope of scct from compile to test

Unfortunately, scct plugin (or coveralls plugin) appends scct library in compile scope. Maybe it's different from what you expected.

```xml
<dependency>
<groupId>com.github.scct</groupId>
<artifactId>scct_2.10</artifactId>
<version>0.3-SNAPSHOT</version>
</dependency>
```

http://oss.sonatype.org/content/repositories/releases/com/github/cb372/cacheable-core_2.10/0.1/cacheable-core_2.10-0.1.pom

see also: https://github.com/mtkopone/scct/issues/54