Fix/larger builds

When working on larger projects with build times in the hours it is nice to have some ways to avoid re-building the code and avoid re-processing the logs. These commits add some command line options that are consumed by vizmake.py before they reach make. These options can tell vizmake.py to not re-build or not to re-process.

A --logdir option is also added to be able to tell vizmake where to store logs. Larger projects can generate gigabytes of logs and sometimes the /tmp partition can't handle that.

When adding the logdir option we also need to make sure that make has buffers large enough to handle a path passed.

Also in this pull-request are some fixes for issues I ran into while trying this on a large build.

Thanks
Jonas