[GRADLE-2945] Adding exclusions in generated pom
[GRADLE-2945] Adding exclusions in generated pom ( checkstyle build fix)
Replace tab with spaces (style fix)
Merge pull request #274 from ffos:GRADLE_2945
Minor improvements to maven-publish exclusion support

- tabs to spaces
- Added test fixture type for MavenDependencyExclusion
- Avoid unnecessary collection empty checks