Problem with fonts loading, icons are not displayed

per https://mobile.twitter.com/erlyberlytips/status/826899295819423744

### Error

```
[erlyberly] java -jar target/*runnable.jar
Gtk-Message: Failed to load module "atk-bridge"

(java:22477): Gtk-WARNING **: Unable to locate theme engine in module_path: "adwaita",

(java:22477): Gtk-WARNING **: Unable to locate theme engine in module_path: "adwaita",
Feb 02, 2017 6:18:55 PM com.sun.javafx.css.StyleManager loadStylesheetUnPrivileged
INFO: Could not load @font-face font [jar:file:/media/arathunku/szklanki/Applications/erlyberly/target/erlyberly-0.6.9-SNAPSHOT-runnable.jar!/erlyberly/SourceCodePro-Medium.ttf]
```


### Versions

#### OS
```
[erlyberly] uname --all
Linux arath-local 4.9.3-200.fc25.x86_64 #1 SMP Fri Jan 13 01:01:13 UTC 2017 x86_64 x86_64 x86_64 GNU/Linux
```

Fedora 25 with i3wm, all latest updates

#### java:

```
[erlyberly] java -version
java version "1.8.0_121"
Java(TM) SE Runtime Environment (build 1.8.0_121-b13)
Java HotSpot(TM) Server VM (build 25.121-b13, mixed mode)
```

#### git:

```
[erlyberly] git rev-parse HEAD
d7615c877dffcd038e3ecd7a75a58e9902b86999
```

### Build

```
[erlyberly] JAVA_HOME=/usr/java/jdk1.8.0_121 ./mvnw clean compile install assembly:single && java -jar target/*runnable.jar
```

I've got SourceCodePro installed from https://github.com/adobe-fonts/source-code-pro via

```
sudo dnf install adobe-source-code-pro-fonts
```

I probably won't be able to help much here (java :see_no_evil:) and I don't really mind the lack of icons as long as labels are there but I'll try to look into the code that's loading the fonts

_______________

Thank you for creating erlyberly! :heart: