shamelessly steal entire implementation from any-promise

[jamestalmage]

any-promise is just very well thought out, there's no point to reinventing the wheel here.

Adds all the following features:

• require('any-observable/implementation') - returns a string containing the implementation name.

• Allows you to register the constructor explicitly.

  require('any-observable/register')('my-observable', {Observable: ObservableConstructor});

• Automatically handles es6 style exports (named or default) - Fixes #7:

  var lib = require(implementation);
  var Observable = lib.Observable || lib.default || lib;

• Creates a global registration, even if any-observable is not deduped - Fixes #6

• Global registration can be disabled using opts.global

  require('any-observable/register')('zen-observable', {global: false});

• Provides a browser shim - Fixes #4
• Just uses rxjs/Observable (minimal) - Fixes #3

[sindresorhus]

Good idea! I naively thought I could do it simpler than any-promise initially.

[sindresorhus]

Automatically handles es6 style exports (named or default)

This is not part of any-promise, right? If true, we should document it.

[jamestalmage]

Allows you to register the constructor explicitly.

That's already part of any-promise. See the advanced section

Automatically handles es6 style exports (named or default)

any-promise only does the following:

var Promise = lib.Promise || lib;

we do:

var Observable = lib.Observable || lib.default || lib;

I haven't seen any implementations where that's actually useful yet, just seemed to be sensible - if they export a default - use that.

[sindresorhus]

Ok, cool.