Follow Scala versioning convention

[guersam]

Now we'll go with single API level as discussed in #43, so how about removing API level from our version number and follow Scala's major.minor.bugfix convention instead?

[pocorall]

After closed the issue #43, I found an additional issue about versioning the library.

Most of the developed app will target below the Android 4.1; and these project usually depends on minimum supported version of Android library, because it prevents mistakenly using newly added features in recent versions of Android.

If Scaloid releases only one version that contains all of the helper methods that is available at the most recent version, developers will takes risk of NoSuchMethodError, and should always check availability manually for every method calls.

I think that Scaloid still needs to be released for multiple versions of Android library.

[guersam]

It makes sense.

How about having androidAPILevel annotation with a SBT plugin which checks API compatibility according to the project's minSdkVersion at compile time?

[guersam]

Just a little possibility.. not sure of the implementation about automatic checking yet. But won't be the annotation visible in IDEs at least?

[guersam]

Also have an idea about the macro based re-implementation for class/helper generation which automatically wraps provided Android SDK in classpath, but it'll result in the lack of IDE support.

[pocorall]

It will be nice if a macro makes proper exception when a missing method is accessed.

But I'd like to lower the priority of this issue, because specifying Android version on Scaloid is not too much burden for both Scaloid users and developers(we).