Alignments

Mirrors the functionality for treebanks for translation alignments.

Reports need arguably more work - depends on what we are trying to show there (just the same as with treebanking)

This leads to new routes, treebank or alignment mode needs now explicitly specified.
Most of the code is shared, much of it has been moved to the `Common` module.
Basically the whole application has been renamed/renamespaced - thus the impressive amount of additions, which is a bit misleading, wasn't that much work. This adds fuel for #14.

Much boilerplate like code and many many files. In most cases it's enough for the `Alignment` or `Treebank` code to hook into one of the `Common` classes and change maybe a method or two.

Quite cool, all in all.