The ornamental design for a needleholder, as shown and described.
FIG. 1 is a left side isometric view of a needle holder in accordance with the new design;
FIG. 2 is a left side elevation view thereof;
FIG. 3 is a right side elevation view thereof;
FIG. 4 is a top isomeric view thereof; and
FIG. 5 is a bottom isometric view thereof;
FIG. 6 is a front isometric view thereof; and,
FIG. 7 is a rear isometric view thereof.
The broken lines shown in FIGS. 1-7 immediately adjacent the shaded areas represent the bounds of the claimed design, while all other broken lines shown in FIGS. 1-7 are directed to environments and are for illustrative purposes only; the broken lines form no part of the claimed design.