Fix typos (#220)

* fix typos in expand.go

* fix typos in README

Author: mrs1669

README.md

@@ -87,7 +87,7 @@ envman run bash -c 'echo "Environment test: $MY_TEST_ENV_KEY"'
 Add/store an environment variable:
 
 ```
-envman add --key MY_SECERT_ENV_KEY --value 'this is a secret value' --sensitive
+envman add --key MY_SECRET_ENV_KEY --value 'this is a secret value' --sensitive
 ```
 
 *Why `bash -c` is required? Because `echo` in itself

env/expand.go

@@ -14,15 +14,15 @@ type Action int
 const (
 	// InvalidAction represents an unexpected state
 	InvalidAction Action = iota + 1
-	// SetAction is an environment variable assignement, like os.Setenv
+	// SetAction is an environment variable assignment, like os.Setenv
 	SetAction
 	// UnsetAction is an action to clear (if existing) an environment variable, like os.Unsetenv
 	UnsetAction
 	// SkipAction means that no action is performed (usually for an env with an empty value)
 	SkipAction
 )
 
-// Command describes an action performed on an envrionment variable
+// Command describes an action performed on an environment variable
 type Command struct {
 	Action   Action
 	Variable Variable
@@ -125,7 +125,7 @@ func GetDeclarationsSideEffects(newEnvs []models.EnvironmentItemModel, envSource
 			delete(evaluatedNewEnvs, command.Variable.Key)
 		case SkipAction:
 		default:
-			return DeclarationSideEffects{}, fmt.Errorf("invalid case for environement declaration action: %#v", command)
+			return DeclarationSideEffects{}, fmt.Errorf("invalid case for environment declaration action: %#v", command)
 		}
 	}
 
@@ -136,7 +136,7 @@ func GetDeclarationsSideEffects(newEnvs []models.EnvironmentItemModel, envSource
 	}, nil
 }
 
-// getDeclarationCommand maps a variable to be daclered (env) to an expanded env key and value.
+// getDeclarationCommand maps a variable to be declared (env) to an expanded env key and value.
 // The current process environment is not changed.
 func getDeclarationCommand(env models.EnvironmentItemModel, envs map[string]string) (Command, error) {
 	envKey, envValue, err := env.GetKeyValuePair()