add unit test for Dot.py replacement()

[Kyle Nitzsche]

1) replacement() should be have a unit test that verifies a range of known invalid dot node names are returned as valid dot node names.

2) the function should have a more descriptive name, perhaps pkg2dotNode(),.

3) Extra credit, the Dot class should perhaps have a dictionary whose key is the node name and whose value is the pkg name.

[Kyle Nitzsche (knitzsche)]

Mike, if interested... a unit test here. Else assign back to me.

[Mike Carifio (carifio)]

Merge proposal https://code.launchpad.net/~carifio/dotdepends/dotdepends-unittests/+merge/114513 addresses testing Dot.replacement(). The other two items should come later when we have more time to do a full unit test for the Dot object. The scaffolding is in place.

[Mike Carifio (carifio)]

Committed dotdepends -r 83, version 3.8.19