The ornamental design for a projector, as shown and described.
FIG. 1 is a front perspective view of a projector of the present invention;
FIG. 2 is a rear perspective view thereof;
FIG. 3 is a front view thereof;
FIG. 4 is a rear view thereof;
FIG. 5 is a first side view thereof;
FIG. 6 is a second side view thereof;
FIG. 7 is a top view thereof; and,
FIG. 8 is a bottom view thereof.
The broken lines shown in the figures are included for the purpose of illustrating environmental elements only and form no part of the claimed design. The dash-dot-dash lines define boundaries of the claimed design and form no part of the claimed design.