Added support for dates with format Ymd.minor.patch

[nazar-pc]

Works identical to major.minor.patch.
Fixes #32, fxpio/composer-asset-plugin#185

[nazar-pc]

Can anyone look at this simple PR?

[alcohol]

I am not sure if we want to keep adding more version formats. We already support semver plus a wide range of exotic less used formats. If we add every format everyone comes up with, soon a version won't carry any meaning anymore.

[nazar-pc]

This is basically improving support for regular major.minor.patch, since major component is currently limited to 5 characters.

[alcohol]

It is limited explicitly to 5 so that it does not overlap with the date(time) regex.

[nazar-pc]

I know, but sometimes we might need to support 6 digits like in linked issues, so why not?

[alcohol]

Well, that is open to discussion. As mentioned in #32, we are not really convinced that this needs "fixing".

@Seldaek is it easy to determine what the impact of this might be on the Packagist database?

[Seldaek]

No it's not easy to tell what the impact would be.. and since it just is to support an external package versioning scheme that isn't even PHP, I would tend to say it's not really our problem. The assets install plugin should make sure it provides valid version identifiers to Composer. Should be as easy as replacing dots by dashes if you see a large version number that looks like a date?