Windows script fix

[sake92]

This PR fixes most of the issues with using CBT on Windows:

• cache strings are now platform independent as far as they can, by using pip(unixPath: String) (path-independent-path, just converts slashes to backslashes)
• batch script is now working properly and is usable

Some minor issues left:

• improve Nailgun support, java.net.SocketException: Connection reset
• time function
• nailgun log files are impossible to write to, when ng-server is up (.. >> %nailgun_out% 2>> %nailgun_err%)
• eval can't be used with single-quotes since CMD treats them specially... You can use double-quotes but then you can't use String literals 😄

[CLAassistant]

All committers have signed the CLA.

[cvogt]

great stuff :)