- fixed getParseTreeNodes
- fixed getting name for TypeNode

Chloe environment building

See merge request !4

- some more class stuff

- added CompEnv, which is a special enviornment for CompNode where it
also stores the imported stuff and the package name, so you can search
the globalEnv with those as well
- added type linking to ClassNode, where it checks the extends and
implements classes/interfaces and makes sure that they are real, and
stores them as the nodes in ClassNode

- can now successfully check that class has at least one constructor
- added rule fixing `this.x = 123;` in `J1_publicfields.java`
- cleaned up Test.py a bit more