Fixed Compiling with Visual Studio 2015

[hhyyrylainen]

When I tried to compile on windows 10 and Visual Studio 2015 I got the following error:

c:\projects\caudio\caudio\include\cAudioString.h(53): error C2664: 'int WideCharToMultiByte(UINT,DWORD,LPCWCH,int,LPSTR,int,LPCCH,LPBOOL)': cannot convert argument 3 from 'const char *' to 'LPCWCH'
3>  c:\projects\caudio\caudio\include\cAudioString.h(53): note: Types pointed to are unrelated; conversion requires reinterpret_cast, C-style cast or function-style cast
3>c:\projects\caudio\caudio\include\cAudioString.h(64): error C2664: 'int MultiByteToWideChar(UINT,DWORD,LPCCH,int,LPWSTR,int)': cannot convert argument 5 from 'char *' to 'LPWSTR'
3>  c:\projects\caudio\caudio\include\cAudioString.h(64): note: Types pointed to are unrelated; conversion requires reinterpret_cast, C-style cast or function-style cast
3>c:\projects\caudio\caudio\headers\cOpenALUtil.h(8): fatal error C1083: Cannot open include file: 'OpenAL/al.h': No such file or directory

I was able to fix those errors and successfully compile with these changes.

I didn't remember I had this open so I accidentally included a linux linker fix here as well.

[xerpi]

I can confirm this made it able to compile in Visual Studio 2013.