* Changed FileStrings so that it doesn't have to be updated every time the file string format changes. The format is now one line per piece of metadata, then a blank line, then the string data. If additional metadata is added later then this will automatically support it.
* Renamed the dataSource.strings service to dataSource.strings.customised, and renamed its get() method to getCustomisedString().
* Changed the semantics of dataSource.strings.customised so that it no longer looks for a default string if it can't find a customised one (and thus removed getDefaultString).
* Abstracted the Generic output module even more. It now consists of output.generic (a service instance with its own constructor) and dataSource.strings (a pure service), the latter of which is a wrapper around dataSource.strings.customised and dataSource.strings.defaults.
* Updated Coses to work with the new dataSource.strings insterface.
* Removed the test app DataSource::ConsoleStrings and DataSource::HTTPStrings files, since they were redundant with the default output files.
* Removed all the default strings in the CosesEditor and Login components since they are pretty pointless.
* Factored out the call to dump() in the GenericOutputs module.
* Changed setString in the MySQL string data source so that it will now add a blank string (it used to delete the string if it was blank, but that meant that it was not possible to customise strings away).
* Added a piece of metadata to strings: their version number.
* Updated the customised string data source stubs to mention the version data now stored with all strings
* Added a getAllStringVersions method to the customised strings data source which returns all the string names and their version numbers.
* Made the customised strings data source check the version number of every string in its database during setupInstall to make sure that they are all up to date, version-wise. If any are out of date, the user is notified.
* Added support for the new version column to the MySQL version of the customised string data source.
* Updated the increasingly misnamed CosesEditor to support the versioned strings stuff.
* Factored out some code in the CosesEditor.
* Added version information to all default strings. All default strings are now at version 1.
* Fixed a typo in a FileStrings dump statement.
* Fixed the calls to setProgress in the MySQL user and strings data sources and in the user field factory to use the correct syntax (a parsable dotted string instead of unlocalisable plain English).
* Updated the Generic output module's documentation to match what now happens.
