Ability to import libraries

[Chapoly1305]

Is your feature request related to a problem? Please describe.
The Ghydra tool prompts users to locate missing .so libraries when loading an executable. This feature allows users to:

• Choose paths for required libraries
• Easily examine library functions when encountered in the project
• Understand function implementations (e.g., popen) by referencing the loaded libraries

At this moment, the Cutter would only provide information at function name level if it came from an external library.

Meanwhile, the Ghydra may load the libraries as Import, and allows conveniently review the function.

1. When click on the function of external, it firstly shows undecompiled state, just like the Cutter.
2. The user may choose Go to External Location, and trigger an analysis prompt.
   
3. The external library will be decompiled and user may now see its logic.
   

Describe the solution you'd like
The Cutter shall allow user to choose a path of dependencies, or prompt user to choose the .so file just in time when the user attempt to know more about the function (for example, double click on function address or name).

A video example
https://www.youtube.com/watch?v=Avn8s7iW3Rc