Renamings for more consistency in declare.ml.
Renamings for more consistency in declare.ml.

declare_variable -> declare_toplevel_assumption
define_constant -> declare_constant_core

coq/coq,coq/coq,coq/coq,SkySkimmer/coq,Zimmi48/coq,ejgallego/coq,ejgallego/coq,coq/coq,SkySkimmer/coq,Zimmi48/coq,ejgallego/coq,SkySkimmer/coq,Zimmi48/coq,ejgallego/coq,SkySkimmer/coq,Zimmi48/coq