fix some golint warnings

Author: PeterIvanov

common.go

@@ -6,19 +6,34 @@ var (
 	// When handling is required, it is best to use custom error types with both standard and custom traits.
 	CommonErrors = NewNamespace("common")
 
+	// IllegalArgument is a type for invalid argument error
 	IllegalArgument      = CommonErrors.NewType("illegal_argument")
+	// IllegalState is a type for invalid state error
 	IllegalState         = CommonErrors.NewType("illegal_state")
+	// IllegalFormat is a type for invalid format error
 	IllegalFormat        = CommonErrors.NewType("illegal_format")
+	// InitializationFailed is a type for initialization error
 	InitializationFailed = CommonErrors.NewType("initialization_failed")
+	// DataUnavailable is a type for unavailable data error
 	DataUnavailable      = CommonErrors.NewType("data_unavailable")
+	// UnsupportedOperation is a type for unsupported operation error
 	UnsupportedOperation = CommonErrors.NewType("unsupported_operation")
+	// RejectedOperation is a type for rejected operation error
 	RejectedOperation    = CommonErrors.NewType("rejected_operation")
+	// Interrupted is a type for interruption error
 	Interrupted          = CommonErrors.NewType("interrupted")
+	// AssertionFailed is a type for assertion error
 	AssertionFailed      = CommonErrors.NewType("assertion_failed")
+	// InternalError is a type for internal error
 	InternalError        = CommonErrors.NewType("internal_error")
+	// ExternalError is a type for external error
 	ExternalError        = CommonErrors.NewType("external_error")
+	// ConcurrentUpdate is a type for concurrent update error
 	ConcurrentUpdate     = CommonErrors.NewType("concurrent_update")
+	// TimeoutElapsed is a type for timeout error
 	TimeoutElapsed       = CommonErrors.NewType("timeout", Timeout())
+	// NotImplemented is an error type for lacking implementation
 	NotImplemented       = UnsupportedOperation.NewSubtype("not_implemented")
+	// UnsupportedVersion is a type for unsupported type error
 	UnsupportedVersion   = UnsupportedOperation.NewSubtype("version")
 )

type.go

@@ -115,6 +115,7 @@ func (t *Type) String() string {
 	return t.FullName()
 }
 
+// MarshalText implements encoding.TextMarshaler
 func (t *Type) MarshalText() (text []byte, err error) {
 	return []byte(t.String()), nil
 }