Update Example: Positioning of Skeleton

Its better to set X and Y of the skeleton then setting X and Y of the root bone.
Merge pull request #76 from AKnopf/patch-1

Update Example: Positioning of Skeleton
Fixed Skeleton_setAttachment("slotname", 0).
Merge remote-tracking branch 'origin/master'
Not relying only on first material anymore
Merge pull request #78 from aviktorov/master

Spine-tk2d runtime bugfix with shared materials
Prevent mesh from temporary disappearing in Unity Editor
Merge pull request #79 from Yonsh/patch-2

Prevent mesh from temporary disappearing in Unity Editor
Merge branch 'master' into monogame