Code and documentation cleanup

src/qir/QIRLanguage.java

src/qir/ast/QIRApply.java

src/qir/ast/QIRDBNode.java

src/qir/ast/QIRExternal.java

src/qir/ast/QIRIf.java

src/qir/ast/QIRLambda.java

src/qir/ast/QIRRootNode.java

src/qir/ast/QIRTruffleNode.java

src/qir/ast/QIRVariable.java

src/qir/ast/data/QIRLcons.java

src/qir/ast/data/QIRLdestr.java

src/qir/ast/data/QIRList.java

src/qir/ast/data/QIRLnil.java

src/qir/ast/data/QIRTable.java

src/qir/ast/data/QIRTcons.java

src/qir/ast/data/QIRTdestr.java

src/qir/ast/data/QIRTnil.java

src/qir/ast/data/QIRTuple.java

src/qir/ast/expression/QIRBaseValue.java

src/qir/ast/expression/QIRBigNumber.java