Typeface making impossibile to include custom library if used inside them
Hi, first of all thanks for the awesome job you've made with this library.

I'd like to report to you a strange behaviour that I've encoutered while working with it inside a custom library that I'm currently working on. 

## The error
The situation is the following:

**1**. I have a custom library, let's call it `library`, which has the following code inside its `build.gradle` file:
```groovy
dependencies {
    compile 'com.mikepenz:iconics-core:2.8.2'
    compile ('com.mikepenz:fontawesome-typeface:4.7.0.0'){transitive = false}
    // I also tried using compile 'com.mikepenz:fontawesome-typeface:4.7.0.0@aar' instead but it does not change anything
}
```

This library is uploaded to a private maven repo with the following id: `com.mycompany:library:1.0.0`

**2**. I have an application project which uses this library inside its dependencies in the `build.gradle` file:
```groovy
dependencies { 
    compile 'com.mycompany.library:1.0.0'
}
```

**3**. Once i try to compile the application project, the compilation throws the following error:
```java
Error:A problem occurred configuring project ':app'.
> Could not resolve all dependencies for configuration ':app:_debugApkCopy'.
   > Could not find Android-Iconics:library-core:unspecified.
     Required by:
         project :app > com.mycompany:library:1.0.0 > com.mikepenz:fontawesome-typeface:4.7.0.0
```

## Searching for a solution
I've searched the whole web for a solution to this, also reading the other issues that have been opened more than a year ago, and looking trough the code of bot the core library and the typeface, i realized that inside the typeface library's `build.gradle` file there is the following line of code:
```groovy
dependencies {
    compile project(':library-core')
}
```

So, I've made some researches tryouts and found out that when `library` is included inside the application project, all of its dependencies are marked as `transitive = true`, so even `com.mikepenz:fontawesome-typeface:4.7.0.0` is marked as `transitive = true`, which makes it throw the error. This does not happen if the library is included as an aar file (using `compile 'com,mycompany:library:1.0.0@aar`) because whole of its dependencies are set to `transitive = false`.
I even tried to set `com.mikepenz:fontawesome-typeface:4.7.0.0` as `transitive = false` inside `library`, but it gets overwritten during the inclusion inside the application project.

## A possibile solution
I've come to the conclusion that the only way to solve this problem is to remove the following line of code from the `build.gradle` file of the typeface libraries
```groovy
dependencies {
    compile project(':library-core')
}
```
and replace it with the following equivalent line
```groovy
dependencies {
    compile 'com.mikepenz:iconics-core:2.8.2'
}
```
I'm aware that this will make all the typeface libraries a little harder to maintain, due to having to change the core library version each time that it is updated, but I'm 98% sure that this would solve all the problems that many users had experienced in the past. Also, this would make all the typeface libraries totally usable either using the `aar` format or not, without any problem in specific cases.

**P.S.** Please excuse me for my bad english.