Add dedicated error classes for the different ways filenames can be invalid

[jwodder]

The exceptions raised by parse_wheel_filename() should form a class hierarchy with InvalidFilenameError at the top and with child classes for the following conditions:

• Filename does not end in ".whl"
• Filename does not have the right number of hyphen-separated components
• Project name is invalid
• Version contains invalid characters
• Build tag is invalid
• Python/ABI/platform tag contains invalid characters

If multiple error conditions apply to a single filename, which error is raised is unspecified.