Introduce new Param File: dimension.param

Removes the dependency from componentsConfig.param
- useful for other param files
- preparation for PIConGPU 2D
Add Param Change to Changelog

- so we won't forget about this param change (quite important for users)
Typo and Highlight File Names
Merge pull request #134 from ax3l/topic-paramDimension

Introduce new Param File: dimension.param