Pipelines/Builds updates

## What does this MR do?
Adds branch/tag icons in admin view; increase min-width of builds tables

## What are the relevant issue numbers?
#20139

## Screenshots (if relevant)
Branch icons:    
![Screen_Shot_2016-07-27_at_1.29.57_PM](/uploads/2fceddfed5ed1a28d9b7d5e2427cba93/Screen_Shot_2016-07-27_at_1.29.57_PM.png)

Reduce `icon-container` width, before:
![Screen_Shot_2016-07-27_at_5.29.32_PM](/uploads/e3fe38edc262f6460572e20102ef9b6d/Screen_Shot_2016-07-27_at_5.29.32_PM.png)
Reduce `icon-container` width, after:
![Screen_Shot_2016-07-27_at_5.29.03_PM](/uploads/58b82e2c1491672c95dfe35911891891/Screen_Shot_2016-07-27_at_5.29.03_PM.png)

See merge request !5527