Invoke oncreate instead of onupdate on hydration

[frenzzy]

Allows to init third-party libs if app was started on non empty container.

Fixes #588
Refs #589

[codecov]

Codecov Report

Merging #595 into master will not change coverage.
The diff coverage is 100%.

@@          Coverage Diff          @@
##           master   #595   +/-   ##
=====================================
  Coverage     100%   100%           
=====================================
  Files           1      1           
  Lines         136    139    +3     
  Branches       41     42    +1     
=====================================
+ Hits          136    139    +3

Impacted Files	Coverage Δ
src/index.js	100% <100%> (ø)	⬆️

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[jorgebucaran]

@frenzzy Thanks. I'll likely implement this together with #590.

[frenzzy]

But #590 does not fix the issue yet and more focused on introducing new api

[jorgebucaran]

🎉🎉🎉

[frenzzy]

Interesting side effect here:

<div
  oncreate={(element, attributes) => {
    if (attributes !== undefined) {
      console.log('node was hydrated!')
    } else {
      console.log('node was created from scratch')
    }
  }}
/>

[jorgebucaran]

@frenzzy Haha, true, danger zone. 💀