The ornamental design for a vacuumcleaner, as shown and described.
FIG. 1 is a left side view of a vacuum cleaner showing our new design;
FIG. 2 is a right side view thereof; and,
FIG. 3 is a top plan view thereof.
The broken line showing of the remainder of the vacuum cleaner is for illustrative purposes only and forms no part of the claimed design. The contrast in shading techniques represents a contrast in color, with the line shading further representing translucency and the stippling further representing an opaque appearance.