Factor locale id parsing from new() into _parse_local()

Tighten up locale id parsing rules
	Make it clear that extensions aren't yet supported
Be explicit about open mode, and croak if it fails
Modernise package variable declarations
Remove old dist artifacts
Don't pollute namespace with imports
Use Test::File::ShareDir to allow tests to run before installation
Use isa_ok() rather than is(ref(...),...)
Add test file missed fom previous commit

New .gitignore to skip MakeMaker artifacts
Add MANIFEST.SKIP, to allow RELEASE_TESTING to pass
Merge pull request #1 from pmh1wheel/pmh

Locale ID parsing changes