AP_Declination library on 1.8.10


I used AP_Declination library from ArduCopter on 1.0.5 IDE.
This is used to find magnetic declination from lat/lon positions.

After upgrading to 1.8.10 I'm having issues where the IDE can't find the right folder path.

Library path for 1.0.5, /arduino/library/ardupilot/library/AP_Declination

When I try the same for 1.8.10, no library is found.

If I place the library directly into the folder arduino/library/AP_Declination.
The IDE finds the library but all the include's inside AP_Declination.h file is not found because there they are typed "#include /HAL/HAL.h.

Tried manually changing the path when compiling, but as one error is fixed another surfaces.
Anyone have a suggestion on how to fix this?

Please post a link to where we can download this.

Sorry for my late repy, have been away on work.

Link to Ardupilot github repo.