Transformation erroneously replacing all overlay spaces to underscore

Currently, Transformation class is replacing all spaces on parameters to underscore in this line:
https://github.com/cloudinary/cloudinary_java/blob/738b328a9057084097b7e381bf8a6e989cf69b43/cloudinary-core/src/main/java/com/cloudinary/Transformation.java#L723

This is causing some issues, like when I try to use some font name that contains spaces (eg: Roboto Condensed), it replaces with underscores and the URL become invalid (because font is invalid). The same applies to text content (overlay), when using the text `My Text Content` it appears on final Image as `My_Text_Content`.

Example:
```java
cloudinary.url()
.signed(true)
.resourceType("video")
.transformation(new Transformation()
.height(480)
.width(720)
.crop("fill")
.chain()
.color("white")
.overlay("text:Roboto_70_bold:My Text Content"))
.format("jpg")
.generate("video/2130");
```
Results in: