Truffle DSL incompatible changes

[Christian Humer]

Hi folks,

I just pushed some breaking changes to latest version of Truffle-DSL. This
will make some guest language adaptations necessary.

1)  Previously with every DSL node there was an NodeFactory implementation
generated. This is now disabled by default. To create a new node instance
use the new {NodeName}Gen#create instead of the old
 {NodeName}Factory#create. In case you need a NodeFactory implementation
annotate your Node with the new @GenerateNodeFactory annotation. I would
recommend guest language developers to use @GenerateNodeFactory only if
really required (for example for builtin nodes) to save some bits.

2) All methods enclosed in a @TypeSystem must now be static. This is
enforced by the DSL.

3) The singleton used in the generated type system classes is now
deprecated and is going to be removed soon.
To migrate your code change patters like:
  SLTypesGen.SLTYPES.expectInteger(value)
to
  SLTypesGen.expectInteger(value)

Please let me know in case you experience any problems.

- Christian Humer