5.4.2
feature: [tooltip] (1) Make component tooltip inherit cascade correct: itemOption.tooltip -> componentOption.tooltip -> globalOption.tooltip (previous incorrect cascade: itemOption.tooltip -> globalOption.tooltip (2) Enable trigger component tooltip by chart.dispatchAction({ type: 'showTip', legendIndex: 0, name: 'some' });
refact: put all core modules in the core dir. only do export in lib/echarts
chore: reuse noop function from zrender util to reduce redundant code.
fix(type): optimize types for dts bundling
ts: let to const. And add eslint rule "prefer-const".