* Adds task dependenciesInfo to BuildPlugin to generate a CSV file with dependencies information (name,version,url,license)
* Adds `ConcatFilesTask.groovy` to concatenates multiple files into one
* Adds task `:distribution:generateDependenciesReport` to concatenate `dependencies.csv` files into a single file (`es-dependencies.csv` by default)
# Examples:
$ gradle dependenciesInfo :distribution:generateDependenciesReport
## Use `csv` system property to customize the output file path
$ gradle dependenciesInfo :distribution:generateDependenciesReport -Dcsv=/tmp/elasticsearch-dependencies.csv
## When branch is not master, use `build.branch` system property to generate correct licenses URLs
$ gradle dependenciesInfo :distribution:generateDependenciesReport -Dbuild.branch=6.x -Dcsv=/tmp/elasticsearch-dependencies.csv