pilot_mods: load modules from directory and check type and version of each

API:
 int
 pilot_mods_load(char *path, long flags, long appid, short type, short version);

 struct pilot_mods *
 pilot_mods_first(short type, short version);

 struct pilot_mods *
 pilot_mods_next(short type, short version);

 pilot_mods_load looks *.so file inside the "path" directory. If "flags" doesn't contain "FLAGSLAZY" each library is loaded and verify if "PILOT_MODS_INFO" symbol is defined.
 if "appid", or "type", or "version" is not zero, the values inside the "pilot_mods_info" structure is checked.

 pilot_mods_first return the first "pilot_mods" structure availlable.
 pilot_mods_next return the next "pilot_mods" structure availlable.
 if "type", or "version" is not zero, the values inside the "pilot_m
ods_info" structure is checked.

mods API:
 each mods must define a "pilot_mods" structure with "api" which contains a structure of functions and other variables.
 this structure must declared with the name "PILOT_MODS_INFO"
pilot_mods: bugfix on internal functions declaration
pilot_mods: add Licence LGPL v3