Leanplum Inc. is signalling it is ready to go mainstream with the hire of veteran CEO George Garrick. The San Francisco mobile marketing platform company also raised $27 million to enhance its product for building customer loyalty and expand into new markets. The money announced Friday is part of a series D funding that began in 2017, bringing the total round to $47 million, which was led by Norwest Venture Partners and Shasta Ventures Garrick came on as CEO and president in October, but the news…