Syntax highlighting and some code completion for [Space Weather Modelling Framework (SWMF)](http://csem.engin.umich.edu/tools/swmf/) configuration files, such as the BATSRUS `PARAM.in` file. The rules are based on the [SWMF manual](http://csem.engin.umich.edu/tools/swmf/documentation/SWMF.pdf) section 3.2.2.