Methods for caching; CLI

• Implemented concretization with cache and installation with cache
• Implemented methods for spack create cache
• Implemented CLI for Dedal

dedal/bll/SpackManager.py

+import os
+from dedal.model.SpackDescriptor import SpackDescriptor
+from dedal.spack_factory.SpackOperationCreator import SpackOperationCreator
+from dedal.configuration.SpackConfig import SpackConfig
+
+
+class SpackManager:
+    """
+    This class defines the logic used by the CLI
+    """
+
+    def __init__(self, spack_config: SpackConfig = None, use_cache=False):
+        self._spack_config = spack_config
+        self._use_cache = use_cache
+
+    def _get_spack_operation(self):
+        return SpackOperationCreator.get_spack_operator(self._spack_config, self._use_cache)
+
+    def install_spack(self, version: str, bashrc_path=os.path.expanduser("~/.bashrc")):
+        self._get_spack_operation().install_spack(spack_version=f'v{version}', bashrc_path=bashrc_path)
+
+    def add_spack_repo(self, repo: SpackDescriptor):
+        """
+        After additional repo was added, setup_spack_env must be invoked
+        """
+        self._spack_config.add_repo(repo)
+
+    def setup_spack_env(self):
+        self._get_spack_operation().setup_spack_env()
+
+    def concretize_spack_env(self):
+        self._get_spack_operation().concretize_spack_env()
+
+    def install_packages(self, jobs: int):
+        self._get_spack_operation().install_packages(jobs=jobs)