Change the tag for 1.x on npm

[m_gol]

It turns out when doing npm install jquery@1.x, npm actually first recognizes it's a valid semver range and doesn't look at the tag at all. This has recently caused issues for npm itself so they banned such ranges on npm master, 2.0.0 will have this rule enforced.

Therefore, we have to change the 1.x tag to something that isn't a valid semver range. This can be verified via require('semver').validRange(tagName). This should return null.

[m_gol]

We should also remove the current 1.x tag, after a year or two it's going to be banned on npm servers as well.

Perhaps we don't really need a tag since 1.x works fine as a semver range?

[dmethvin]

Once we reversion into *two* packages this won't be an issue. Is it possible to unpublish/remove a tag? If so I don't know how.

[m_gol]

@dmethvin It seems it's not possible now but soon will be; see ​https://github.com/npm/npm/issues/6243

[m_gol]

Migrated to ​https://github.com/jquery/jquery/issues/1793