[minor] tidying for checkstyle
Added commons-configuration dependency
[minor] comment edit
[minor] reset to fail on style warnings
[minor] edit to pass checkstyle tests
[minor] checkstyle fixes
Updated signature file versions
Added help information and screenshot for Checksum type selection
Added warning message to preferences popup (changes in effect after new profile creation only)
[minor] revert to previous sig files so signature changes can go in separate branch