* Implemented ruby comparison version check.
* Added semver package to validate and check version
* Added more tests
* Replaced go-version with semver
* Removing go-version from dependency
* Added check for ruby gem version format
* Updated semver model and patch rewrite process
* Refactoring
* refactor(docker_conf): rename and remove unnecessary options
* feat(rpc): define new API
* fix(cli): change default timeout
* fix(import): fix package names
* refactor(vulnerability): remove old mock
* refactor(utils): remove un-needed functions
* feat(cache): implement cache communicating with a server
* refactor(scan): separate scan function as local scanner
* test(scanner): add tests for ScanImage
* refactor(scan): remove unused options
* test(vulnerability): generate mock
* refactor(server): split a file
* feat(server): implement new RPC server
* feat(client): implement new RPC client
* fix(cache): use new cache interface
* fix(standalone): use new scanner
* fix(client): use new scanner
* fix(server): pass cache
* test(integration): make sure an error is not nil before calling the method
* fix(mod): update dependencies
* test(integration): ensure the image load finishes
* feat(docker): support DOCKER_HOST and DOCKER_CERT_PATH
* chore(mod): update dependencies
* refactor(rpc): remove old client
* feat(server): support old API for backward compatibility
* fix(server): check a schema version of JSON cache
* fix(rpc): add a version to packages
* feat(rpc): add PutImage
* test: rename expectations
* refactor(cache): rename LayerCache to ImageCache
* refactor: rename ImageInfo to ImageReference
* fix(applier): pass image_id to ApplyLayer
* feat(cache): handle image cache
* chore(mod): update dependencies
* refactor(server): pass only config
* feat(cli): add -removed-pkgs option
* refactor(err): wrap errors
