The ornamental design for a storagecontainer, as shown and described.
FIG. 1 is an elevated perspective view of a storage container, showing our new design;
FIG. 2 is a left side view thereof;
FIG. 3 is a right side view thereof;
FIG. 4 is a front view thereof;
FIG. 5 is a back view thereof;
FIG. 6 is a top side view thereof;
FIG. 7 is a bottom side view thereof; and,
FIG. 8 is a perspective view of the storage container attached to a bottle.
The broken lines and the unshaded surfaces bound by broken lines in FIG. 6 represent portions of the storage container and form no part of the claimed design. The broken lines in FIG. 8 depict a bottle that forms no part of the claimed design.