Fix for default text size being set in PX instead of DP

The default text size in ComponentBase was defined as 10 pixels
instead of 10dp, which causes tiny text and does not reflect
the javadoc and the general behavior of setTextSize(...)
diff --git a/MPChartLib/src/main/java/com/github/mikephil/charting/components/ComponentBase.java b/MPChartLib/src/main/java/com/github/mikephil/charting/components/ComponentBase.java
index 7d31d03..d3a1d4d 100644
--- a/MPChartLib/src/main/java/com/github/mikephil/charting/components/ComponentBase.java
+++ b/MPChartLib/src/main/java/com/github/mikephil/charting/components/ComponentBase.java
@@ -36,7 +36,7 @@
     /**
      * the text size of the labels
      */
-    protected float mTextSize = 10f;
+    protected float mTextSize = Utils.convertDpToPixel(10f);
 
     /**
      * the text color to use for the labels