Add <source> path and make class filenames relative to the source path

This fixes gotwarlost/istanbul#50 by giving source paths where Jenkins
can find the source files in order to archive them and paint the source
with proper coverage styles.
Address windows path separator issue
Merge pull request #51 from MeetMe/cobertura-source-paths

Add <source> path and make class filenames relative to the source path
Update changelog, up version add @jhansche as contributor
Up version for real
LcovReporter should forward sourceStore into HtmlReporter
Merge pull request #76 from vojtajina/fix-lcov-reporter

LcovReporter should forward sourceStore into HtmlReporter
Up version, add change log, add @vojtajina as contributor
Add JSON report
Update changelog, up version