Fixed an issue introduced with #722
Deleted obsolete branch for ticket #650
Implemented ticket #650 "Read and write arbitrary ZIP files"
Improved implementation of ticket #650
Reading and writing TARs and GZs is now possible for #650
Reading and writing ZIPs is now possible for #650
Added initial implementation of packArchive() to #650
Added initial implementation to ticket #650
Created branch for ticket #650
Implemented ticket #772 "Create cumulative matrix functions"