feat: GQL-2 -- grammar, plugin, GqlAst, AstBuilder#868

SemyonSinchenko wants to merge 2 commits into

graphframes:maingraphframes/graphframes:mainfrom

SemyonSinchenko:chore-gql-antl4-ast-builderSemyonSinchenko/graphframes:chore-gql-antl4-ast-builderCopy head branch name to clipboard