I added an optional attribute to the "solution" tag named "version".
This attribute can hold values in the form of "1.0.3.4".
This version will be applied to the projects that are build in the compilation process, ignoring the projects that are up to date, allowing to just change the version of the projects that were build instead of changing it to all of them.
The attribute is optional, so if it is not set the build process will work as usual.
Patch file to support this functionality