add `Abstract.follow_with_abstracts`
follow abstract type before checking equality when resolving binops (see #3214)
[java] Added sys.db.Mysql support
[display] skip KAbstractImpl classes for toplevel completion (see #3310)
fix overzealous regex refactoring
add test for KAbstractImpl toplevel completion (closes #3310)
stop wasting travis time on flash8
pipe type parameters through `raw_class_field`
add type parameters to FInstance