Removed external tools code.

Removed all the code and tests to do with external tools.
Logic to fix references.

Added methods to fix assembly references. Included blurb in the readme
about re-writing the references.
Added reference fix logic to console.

Added the logic to fix references to the console.
Removed re-sign after reference fix.

Turns out you don't need to re-sign assemblies after making reference
updates, it doesn't affect the assembly hash.
Strong name signer API complete.

API passing all rules.
Console complete.

Console application functionality complete.