text: Title: [BUG] Long filter values needs to be abbreviated
  Body: **Describe the bug**
  Filters titles with very long values are not abbreviated, resulting in very wide visualizations.
  
  **To Reproduce**
  ```python
  from lux.vis.Vis import Vis
  long_content = "Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat. Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum."
  
  dataset = [
      {"long_attr":long_content, "normal": 3, "normal2": 1},
      {"long_attr":long_content, "normal": 3, "normal2": 1},
      {"long_attr":long_content, "normal": 2, "normal2": 1},
      {"long_attr":long_content, "normal": 4, "normal2": 1}
  ]
  test = pd.DataFrame(dataset)
  vis = Vis(["normal2", "normal",f"long_attr={long_content}"], test)
  ```
  ![image](https://user-images.githubusercontent.com/5554675/109974153-396abd00-7d34-11eb-9ac6-a2121d84cf91.png)
  
  This is also an issue for matplotlib but the results are cutoff: 
  ![image](https://user-images.githubusercontent.com/5554675/109974080-2657ed00-7d34-11eb-9091-9971ae21b711.png)
  
  **Expected behavior**
  We should abbreviate the values on filter. We are in fact doing abbreviation for attribute values and legend. Perhaps there is some shared code that we can reuse across these different abbreviation usages? 
  