add instructions to install wheel into virtual environment

[cash]

Somewhere in the dependency tree is Pillow which requires compiling C code. A lot of user will have trouble with that unless they first install wheel into their virtual environment and get the precompiled binary.

[eugene-yang]

That must be newspaper.
I mostly install dependencies through conda and there were not any issues that popped up.
Are you using native python virtual environment?

[cash]

Using a native python virtual environment without the wheel package causes compiling C code.