Rasbats - Fix compile MSVC++  O3.3.1117 per [Rasbats]

Fix compile MSVC++  O3.3.1117 per [Rasbats]

SettingDialog.cpp  Line 114 & 115 (Capital B to b)
bool AlternatesForAll = m_cbAlternatesForAll->GetValue();

Copy Cutil.h from the main opencpn source to plugins\weather_routing_pi
Renamed the file to Cutil_weather_routing.h
Searched for references to cutil.h and changed

Cutil_weather_routing.h  comment out  roundint function starting at line 65

Change any reference to 'cutil.h' to read 'cutil_weather_routing.h' 
(georef.c)  #include "cutil.h"    to  #include 'cutil_weather_routing.h'
(CMakeLists.txt) in main weather_routing_pi directory, 
add  at line 110  'src/cutil_weather_routing.h'  

Correct compile error in 'BoatPlan.h' : NAN not defined.
Below the 'define's at the head of the file, added:
    #if !defined(NAN)
    static const long long lNaN = 0xfff8000000000000;
    #define NAN (*(double*)&lNaN)
    #endif

Note:MSVC++ debug version does not work well, but Release
does work with new grib_pi plugin and fresh grib files.

Also cmake --build . output shows 30 warnings coming from georef.c
related to  'warning C4101: 'sinth1' : unreferenced local variable'
About 15 are from same line 1003 in georef.c

FS#1135 - Pull request -> Fixed, committed, synced -
Illegal External File Refs fixed
http://opencpn.org/ocpn/flyspray/index.php?do=details&task_id=1135&project=32

NOTE about previous Commit
-The Plugin compiled and worked with Climatology, but not with gribs!!