Enable configuring patches directory path

[siemova]

Currently, the path to the "patches" directory is hard-coded in PatchFileFactory. I want to use ".composer/patches" instead, and I expect others have similar requirements, so it would be helpful to enable configuring that somewhere.

[TomasVotruba]

Hi, that sounds reasonable.

Would you like to contribute this feature?
How would you implement it?

[siemova]

I tried my hand at implementing this using an environment variable. If that is unacceptable for some reason, the alternative appears to be adding an optional parameter to the generate command. Please let me know what you think.

[TomasVotruba]

Thanks for the kickoff. The command option would be better indeed, as clear entry point of the value. Could you handle it?