add "Hello, Flutter" presentation

[hijiangtao]

「Hello, Flutter」 is the slides of a brief recap of Mobile Development and detailed introduction about Flutter and its internals from three aspects (WHAT, WHY and HOW), the slides can be divided into eight parts:

1 / MOBILE DEVELOPMENT RECAP
2 / EXISTING PROBLEMS
3 / WHAT IS FLUTTER
4 / HOW IS FLUTTER
5 / WHY CHOOSE FLUTTER
6 / CODE WITH DART
7 / TAKE AWAY
8 / Q&A

You've read How to contribute right ?

[Solido]

A nice presentation but way too light currently, thx for PR !

[hijiangtao]

Thanks for your comment, I thought an awesome Flutter should contain different levels of contents that’s really awesome, a project only contains things like advanced tutorials shouldn’t be named “awesome”, but is “pro” indeed? :-) From Joe Jiang, https://hijiangtao.github.io/

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在 2019年1月17日，02:28，Robert Felker ***@***.***> 写道： Closed #295. — You are receiving this because you authored the thread. Reply to this email directly, view it on GitHub, or mute the thread.

[hjJunior]

@Solido can u please check my presentation ? If u think could be good I open a PR

https://speakerdeck.com/hjjunior/why-i-chose-flutter

[Solido]

My constrain is that is receive a LOT of PR and I can't add all. Also most of the time people doesn't work together so I received many resources for the same solution. Thus I should raise the level if I want to let the list readable. Also one closed PR doesn't close the doors definitively but yes you need to offer awesomeness in some way :D

[hijiangtao]

Thanks