Add Copyright Notice about drive

[tiwanari]

Here is a list of external libraries.

• com.pileproject:drivecommand:2.1.0
• com.android.support:support-v4:23.2.1
• com.android.support:appcompat-v7:23.4.0
• com.android.support:design:23.2.1
• com.android.support:preference-v7:23.0.1
• com.yahoo.squidb:squidb:2.0.2
• com.yahoo.squidb:squidb-annotations:2.0.2
• com.rejasupotaro:kvs-schema:5.0.0
• co.trikita:log:1.1.5
• io.reactivex:rxandroid:1.2.1
• io.reactivex:rxjava:1.1.6

[tiwanari]

I will leave references for LICENSEs.

• drivecommand/LICENSE
• squidb/LICENSE
• kvs-schema/LICENSE.txt
• log/LICENSE
• RxAndroid/LICENSE
• RxJava/LICENSE

Unknown:

• android/platform_frameworks_support

[tiwanari]

[WIP] I listed LICENSEs.

[tiwanari]

I searched for a good way to show them and found some articles so I leave them here.

Collect manually and show them as Dialog (or WebView)

• (Japanese) DialogFragmentで作るライセンス情報 - Qiita
• "Open source licenses" screen

Collect automatically

• hierynomus/license-gradle-plugin: Manage your license(s)
  • (Japanese) to know how to use the above plugin, see: build.gradleのdependenciesに追加されたライブラリのライセンス情報を出力する - woshidan's blog

UPDATE:
I think we can use both of them.

1. collect copyrights automatically with the bottom way
2. show them with the above way

[tiwanari]

I mistook copyright notice and legal notice... I commented some related to copyright and legal notice should be discussed in another place.

NOTE:

• Copyright Notice is for others' libraries
• Legal Notice is for our application

[tiwanari]

Solved by #57