Update slf4j (1.7.6) and logback (1.1.1)
merge dev_5_0 -D org: PR 915 (Fix for single channel  meas_mode 13 data.)
merge dev_5_0 -D org: PR 941 (Fix the download URL for stable release jars)
merge dev_5_0 -D org: PR 946 (Read internal pyramids from CellSens .vsi data)
merge dev_5_0 -D org: PR 951 (Fix up Bio-Formats POMs)
merge dev_5_0 -D org: PR 952 (Memoization fixes)
merge dev_5_0 -D org: PR 957 (Correctly set Modulo annotations for multi-Image datasets (rebased onto dev_5_0))
merge dev_5_0 -D org: PR 958 (Flex: be more permissive in parsing IFDs and XML (rebased onto dev_5_0))
merge dev_5_0 -D org: PR 960 (Cache OME-XML between ImagePluses (rebased onto dev_5_0))
merge dev_5_0 -D org: PR 966 (Update logging jars)