WIP: Add @material-ui/icons support

[gm666q]

This PR is work in progress.

Related issue: #25

[toliner]

Thanks for your work. Code in this PR help me a lot.

I think that kotlin wrapper of @material-ui/icons should be auto-generated, because there are over 1100 icons.

From material-ui's document

Material Design has standardized over 1,100 official icons, each in five different "themes" (see below). For each SVG icon, we export the respective React component from the @material-ui/icons package. You can search the full list of these icons.

Hand-writing such a large number of wrappers is so hard.
I have an idea how to generate wrapper code:

1. Get list of icons from material-icons's source dir
2. Generate imports.kt based on the list
3. Generate dsl functions (extension functions for RBuilder) for each icons

Here is the example of code-generation, build and publish: https://github.com/justincase-jp/AWS-CDK-Kotlin-DSL
I did it, so I can help you if you want to do code-generation.

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Japanese:
英語が怪しいので日本語で要約

公式ドキュメントによると、Materialのアイコン数は1100以上、スタイルの差も含めたらjsファイルが6672個あるらしい。
手で書くのは流石に無理では？コード生成した方が良いと思います。
Material-uiのソースコードからiconの一覧は取得可能なので、それを使えばできるはずです。
私は別件でKotlinのコード生成 & ビルド & デプロイをやった事があるので、お手伝いできると思います。

[subroh0508]

@toliner Thanks for the suggestion! If you can write to write generator, I welcome your contribution😎

So please send me a Pull Request!

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Japanese:

提案ありがとうございます！自動生成での対応、良いと思います😎
レビューは適宜しますので、Pull Requestを送ってくださると大変嬉しいです！

[gm666q]

I wrote a crude generator in Rust I can share that or rewrite it if you prefer another language. I added remaining icons but didn't test it too much since there is more then 6000 icons. I also updated .gitingore because it wasn't ignoring OS specific files and gradle files correctly (https://github.com/JetBrains/idea-gitignore).