read/pe should handle unaligned section addresses and sizes

[philipc]

The PE file format specifies that sections should be aligned, but Windows still loads them if they are not. We should duplicate the logic that Windows uses.

[philipc]

• example file
• possible method of handling alignment

I don't think there's any official documentation on how to handle this, and llvm-readobj doesn't handle the example file either, so this is a low priority unless you're interested in things like parsing malware.