Add new batch file to build both CodeSnip editions

[delphidabbler]

It's a bit of a faff to always having to run Make twice when building a release. Their could be a release batch file that could do the following:

1. Enforce the use of a version number to be included in the file names.
2. Define VERSION to hold version number passed on command line.
3. Call Make twice, once with PORTABLE defined.