* Remove push and shove router documentation which is maintained in the
user documentation.
* Remove coding_style_policy.pdf since it is know automatically generated
with the developers documentation and linked on the KiCad website.
* Merge the contents of rules_for_capitalization_in_Kicad_UI.txt into
UIPolicy.txt.
* Remove rules_for_capitalization_in_Kicad_UI.txt.