Add missing GetFileVersionInfo*Ex* funcs

[roblabla]

Add a handful of missing functions from winver.h, namely GetFileVersionInfo(Size)?Ex(W|A), and the associated constant flags.

[nico-abram]

Relevant header code:

winver.h

DWORD APIENTRY GetFileVersionInfoSizeExA(_In_ DWORD dwFlags, _In_ LPCSTR lpwstrFilename, _Out_ LPDWORD lpdwHandle);
DWORD APIENTRY GetFileVersionInfoSizeExW(_In_ DWORD dwFlags, _In_ LPCWSTR lpwstrFilename, _Out_ LPDWORD lpdwHandle);

BOOL APIENTRY GetFileVersionInfoExA(_In_ DWORD dwFlags,
                                    _In_ LPCSTR lpwstrFilename,
                                    _Reserved_ DWORD dwHandle,
                                    _In_ DWORD dwLen,
                                    _Out_writes_bytes_(dwLen) LPVOID lpData);
BOOL APIENTRY GetFileVersionInfoExW(_In_ DWORD dwFlags,
                                    _In_ LPCWSTR lpwstrFilename,
                                    _Reserved_ DWORD dwHandle,
                                    _In_ DWORD dwLen,
                                    _Out_writes_bytes_(dwLen) LPVOID lpData);

verrsrc.h

/* 
    FILE_VER_GET_... flags are for use by 
    GetFileVersionInfoSizeEx
    GetFileVersionInfoExW
*/
#define FILE_VER_GET_LOCALISED  0x01
#define FILE_VER_GET_NEUTRAL    0x02
#define FILE_VER_GET_PREFETCHED 0x04

/* ----- Types and structures ----- */

typedef struct tagVS_FIXEDFILEINFO
{
    DWORD   dwSignature;            /* e.g. 0xfeef04bd */
    DWORD   dwStrucVersion;         /* e.g. 0x00000042 = "0.42" */
    DWORD   dwFileVersionMS;        /* e.g. 0x00030075 = "3.75" */
    DWORD   dwFileVersionLS;        /* e.g. 0x00000031 = "0.31" */
    DWORD   dwProductVersionMS;     /* e.g. 0x00030010 = "3.10" */
    DWORD   dwProductVersionLS;     /* e.g. 0x00000031 = "0.31" */
    DWORD   dwFileFlagsMask;        /* = 0x3F for version "0.42" */
    DWORD   dwFileFlags;            /* e.g. VFF_DEBUG | VFF_PRERELEASE */
    DWORD   dwFileOS;               /* e.g. VOS_DOS_WINDOWS16 */
    DWORD   dwFileType;             /* e.g. VFT_DRIVER */
    DWORD   dwFileSubtype;          /* e.g. VFT2_DRV_KEYBOARD */
    DWORD   dwFileDateMS;           /* e.g. 0 */
    DWORD   dwFileDateLS;           /* e.g. 0 */
} VS_FIXEDFILEINFO;

According to the contribution guidelines shouldn't the struct and consts go in a new verrsrc.rs file?

All definitions go into the source file that directly maps to the header the definition is from. 

Also, the parameter name for GetFileVersionInfoExA and GetFileVersionInfoExW lptstrFilename seems to not match the header (lpwstrFilename)
Same thing for GetFileVersionInfoSizeExA and GetFileVersionInfoSizeExW

Other than that, LGTM

[roblabla]

Thanks for the review, will fix.

[roblabla]

I took the opportunity to fix some other small mistakes in the winver.rs files (that were backward-compatible). I applied the requested changes, and further changed *mut c_void to LPVOID so it matches the header, and reordered some functions so they appear in the same order as the windows header files.

[nico-abram]

I think CI failed because of using use crate:: (I think it might not be supported by the MSRV of 1.6)

[roblabla]

This is ready now.

[nico-abram]

LGTM

[roblabla]

#906 turns out there's an existing PR that's more complete than this one. This should be merged instead.