Golub Capital,  www.golubcapital.com . (PRNewsFoto/Golub Capital)NEW YORK, April 17, 2018 /PRNewswire/ — Middle market private companies in the Golub Capital Altman Index experienced year-over-year revenue growth of 10.96% and earnings growth of 6.22% during the first two months of the first quarter of 2018. This compares to year-over-year revenue…