Added check for plugin addition

before plugin is added to the config, cli.py checks if the package does exist and if the name is correct (capital letters,...)

cbpi/__init__.py

@@ -1 +1 @@
-__version__ = "4.0.1.15"
+__version__ = "4.0.1.16"

cbpi/cli.py

@@ -218,7 +218,18 @@ def plugins_add(package_name):
             return
         return
 
+    installation = True
     try:
+        try:
+            p_metadata= metadata(package_name)
+            p_name=p_metadata['Name']
+            if p_name != package_name:
+                print("Error. Package name {} does not exist. Did you mean {}".format(package_name,p_name))
+                installation = False
+        except Exception as e:
+            print("Error. Package {} cannot be found in installed packages".format(package_name))
+            installation = False
+        if installation:
             with open(os.path.join(".", 'config', "config.yaml"), 'rt') as f:
                 data = yaml.load(f, Loader=yaml.FullLoader)
                 if package_name in data["plugins"]: