Removed visit functions for abstract AST nodes.
Removed visit functions for abstract AST nodes.

ruchevits/solidity,shahankhatch/solidity,arkpar/solidity,debris/solidity,chriseth/solidity-doc-test,gluk256/solidity,ruchevits/solidity,ruchevits/solidity,douglas-larocca/solidity,vaporry/solidity,ruchevits/solidity,chriseth/solidity,LianaHus/solidity,ethers/solidity