Makefile: Fix OBJS LDFLAGS order
Drop p2p support.

I have doubts it was used by many. No time should be wasted in refactoring it.
A clean reimplementation should be considered in the future. For me this doesn't seem like a
very useful feature these days. Ad hoc games can be played over FICS as a guest or lichess should FICS be down.
mail fix
Delete CVS dir
Drop dead code: altbufferedconnection class.

Appears to have been experimental, never used though.
Delete fallbackconnection.

Revisit this in the future it may be useful if more visible to the user.