This part shall be liberally construed and applied to promote its underlying purposes and policies. This part should be construed according to its purposes, which are to:
(1) Avoid jurisdictional competition and conflict with courts of other states in matters of child custody which have in the past resulted in the shifting of children from state to state with harmful effects on their well-being;
(2) Promote cooperation with the courts of other states to the end that a custody decree is rendered in that state which can best decide the case in the interest of the child;
(3) Discourage the use of the interstate system for continuing controversies over child custody;
(4) Deter abductions of children;
(5) Avoid relitigation of custody decisions of other states in this state; and
(6) Facilitate the enforcement of custody decrees of other states.