Change some marcos and API calls to be suitable for windows

[unbadfish]

My editor deleted some trailing spaces, which makes a lot of differences between old file and new file. The main edits are simple:

1. in synctex_parser_utils.c: L 168-169

As synctex is based on 8 bits characters, including UTF8, not 16 bits nor 32 bits, change default API calls (auto expand to W) to As.

synctex/synctex_parser.h

Lines 91 to 93 in 9176177

	* file system, assuming that it is based on
	* 8 bits characters, including UTF8,
	* not 16 bits nor 32 bits.

- last_component = PathFindFileName(string);
- last_extension = PathFindExtension(string);
+ last_component = PathFindFileNameA(string);
+ last_extension = PathFindExtensionA(string);

2. in synctex_parser_utils.h: L 90
   GCC's __attribute__ extension is not useable in windows. re-define it to dummy.

https://stackoverflow.com/questions/28411283/dealing-with-attribute-in-msvc

#	if defined(_MSC_VER)
-#		define SYNCTEX_ATTRIBUTE_FORMAT_PRINTF(STRING_INDEX, FIRST_TO_CHECK) ATTRIBUTE_FORMAT_PRINTF(STRING_INDEX, FIRST_TO_CHECK)
+#		define SYNCTEX_ATTRIBUTE_FORMAT_PRINTF(STRING_INDEX, FIRST_TO_CHECK)
#	else
#		define SYNCTEX_ATTRIBUTE_FORMAT_PRINTF(STRING_INDEX, FIRST_TO_CHECK) __attribute__((__format__ (__printf__, (STRING_INDEX), (FIRST_TO_CHECK))))
#	endif

[unbadfish]

When upgrading synctex in https://github.com/sumatrapdfreader/sumatrapdf , I came up with some compile error. This PR is mainly from sumatrapdfreader/sumatrapdf@374896d