Factor DistributionPoints.exists() to DistributionPoint.

Make DistributionPoints.(u)mount() dependent on whether the
DistributionPoint implements that method.

Fix a type.
Fix excessive line length.
Add casper.Casper class for getting results of casper.jxml.
Finalize preliminary work on casper class.
Implement JDS distribution point.

Currently only supports copy_pkg.
DistributionPoints does not recognize type JDS yet.
Update __repr__ methods.
Update __repr__ method to display more information.

Update docstrings.
Handle explicit and implicit distribution point configuration, and JDS.

For "old-style" DP declarations, use existing method of using
distributionpoints results to populate connection arguments.

For "new-style" DP declarations, pull information from the
JSS.repo_prefs property.

Add helper methods for adding/removing DP's from DistributionPoints.

Add JDS DP's to DistributionPoints.
Update CHANGELOG.
Update documentation to show direction with JDS (cannot do everyting.)

PEP8 cleanup as well.
Add in connection parameter checking for DistributionPoint subclasses.
Add in JDS.exists() and JDS.exists_with_casper() methods.
Minor formatting and documentation.
Bump version, add documentation.
Implement JDS copy_script method. Refactor to type-codes. Other fixes.

While broken, implemented JDS.copy_script. (It includes HTML form
boundaries in script file upon posting.)

Adds type-codes for file types, and uses global lists for collections of
file types.

DistributionPoints.copy(_pkg)(_script) now have defaulted id_ parameter
to work with JDS' copy methods.

Add documentation for above.

Fix reference to jss object in JDS.exists()

Implement JDS.exists_with_casper(). Algorithm is unsatisfactory, so
expect it to change.
Rewrite algorithm for JDS.exists_with_casper() to be more complete.
Update README documentation.
Updates to README.md
Move README to wiki.