New project appears after using Android ADT latest development tool AppCompat V7 what is he?

Android developers have recently discovered that after updating ADT to 22.6.0, a new Setup project will appear, and the contents of the appcompat_v7 are created. and create a new content that will appear. What the hell is going on here? The original appcompat_v7 is Google's own one of the compatibility package, is a support library, can make more than 2.1 full use of the 4.0 version of the interface. The following let the author take you slowly approached this problem and solve it.

You will find that after the project has been created, in addition to the "Test" project we created, there is a package called "Appcompat_v7", and the package shows an error (red X), while the "test" package displays a red exclamation mark. Workspace.

Workaround: If you're still brooding over the APPCOMPAT_V7 package, I'll tell you how to build a project without the APPCOMPAT_V7 package. Since the APPCOMPAT_V7 package is a support library that allows more than 2.1 to use the 4.0 version of the interface, then we have to build the project to select the Minimum SDK above Android4.0 do not need this support library? The result proves that our idea is right.