Goo Goo Dolls continue to evolveJohnny Rzeznik, singer/guitarist in the Goo Goo Dolls, is no songwriting neophyte. He’s been the band’s chief songwriter throughout its two-decade history and he’s written or co-written an enviable number of hit songs, with tunes like “Iris,” “Slide” and “Name” among his dozen top 10 adult top 40 hits.But over the course of writing and recording the ninth Goo Goo Dolls studio CD, Rzeznik said he found he still can learn about the art of songwriting, particularly in terms of learning how to deal with the times when ideas aren’t flowing.“I think that’s the biggest