Adding migration of files

When migrating from v1 to v2, there are potentially a number of files
renames that have to occur. This introduces a versioncake command
migrate that makes that process easier:

versioncake migrate [path/to/views]

The command takes an optional path where it should look for versioned
template files.
Updating changelog for migration script addition
Merge branch 'feature-migrate_tool_from_v1_to_v2'