fixed #80

BandwidthTestAction implemented
The action requires an integer as body for execution.
The body stands for the size (in MB) of test file that will be returned.

The path for the testfiles is:
<serverResourcesPath>/de/cismet/cids/tools/bandwidthTest/
The names of the test files have this shema: <sizeInMB>MB.zip
Merge branch 'feature/80-BandwidthTestAction' into dev