server: Added searchFile method
storage: Added StorageManagerFactory to create StorageManagers with the correct configuration
app: BugFixed. "opencgaHome" was not found.
server: File fetch accepts multiple files and multiple regions.
server: Some changes in file-fetch. Variant-fetch enabled.
server: FileWSServer.index now reads a backend.
storage: Bugfix in IndexedAlignmentDBAdaptorTest
storage: Mongo alignments coverage histogram now returns "features_count" instead of "feature_count"