Merge branch 'master' of https://github.com/kaelzhang/neuron
converter: add transformer 'remove-wrapper'
upgrade: nr-define: will check whether is AST_Call;
upgrade: add a transformer 'remove-wrapper' to remove NR.define wrapper of a neuron module
upgrade: tranformer/nr: distinguish global DP and local DP, avoiding naming conflict
upgrade/analyzer: add configurations for AST_Toplevel
upgrade: tranformer/nr: distinguish global DP and local DP, avoiding naming conflict
upgrade: add test case for transformer/exports.js