Fix stable tag for prefix semver

No longer adds an extended version when prefix semver is being used, and the current commit has been tagged with the correct prefix.

Update version of jgit

Bumps jgit to 4.4.1.201607150455 from 3.4.1.201406201815 . Jgit 4 handles symlinks better, reducing the number of erroneous '.dirty' suffixes appended to versions built from repositories that have symlinks.

Add semverVersionTopoPrefix

• Add a semverVersionTopoPrefix method, which does both toposemver and prefixsemver

v0.6.0

• Breaking: rename topoSemverVersion() to semverVersionTopo()
• Breaking: rename prefixSemverVersion() to semverVersionPrefix()

v0.5.0

• BREAKING: printVersion and printStatus task not automatically applied.
  • Use addPrintVersionTask() and addPrintStatusTask() to do so

v0.4.1

Add the version object.