Add all message functions to "define_pmake"

[daar]

Currently the message functions are directly generating output to the command-line. What is proposed to create actions, attached to a pmake definition that could be created in the define_pmake function. By attaching these pmake definitions to packages, one can at least create the output on the first call of a package from a certain pmake definition.

package -> pmake definition -> message action

procedure message(mode: msgMode; msg: string);
procedure message(msg: string);
procedure messagefmt(mode: msgMode; msg: string; const args: array of const);
procedure messagefmt(msg: string; const args: array of const);

[daar]

Related to #39