BUG: Fixed cygwin module creation rules. Modules should not have the "cyg"...

BUG: Fixed cygwin module creation rules.  Modules should not have the "cyg" prefix by default.  Removd soname flags from creation rules because they are never used on this platform.

Modules/Platform/CYGWIN.cmake

 SET(CMAKE_SHARED_LIBRARY_CREATE_C_FLAGS "-shared -Wl,--export-all-symbols -Wl,--enable-auto-import")
+SET(CMAKE_SHARED_MODULE_CREATE_C_FLAGS ${CMAKE_SHARED_LIBRARY_CREATE_C_FLAGS})
 SET(CMAKE_DL_LIBS "-lgdi32" )
 SET(CMAKE_SHARED_LIBRARY_PREFIX "cyg")
 SET(CMAKE_SHARED_LIBRARY_SUFFIX ".dll")
+SET(CMAKE_SHARED_MODULE_PREFIX "lib")
+SET(CMAKE_SHARED_MODULE_SUFFIX ".dll")
 SET(CMAKE_IMPORT_LIBRARY_PREFIX "lib")
 SET(CMAKE_IMPORT_LIBRARY_SUFFIX ".dll.a")
 # no pic for gcc on cygwin
@@ -9,15 +12,18 @@ SET(CMAKE_SHARED_LIBRARY_C_FLAGS "")
 SET(CMAKE_SHARED_LIBRARY_CXX_FLAGS "")
 SET(CMAKE_EXECUTABLE_SUFFIX ".exe")          # .exe
 
+# Modules have a different default prefix that shared libs.
+SET(CMAKE_MODULE_EXISTS 1)
+
 SET(CMAKE_FIND_LIBRARY_PREFIXES "cyg" "lib")
 SET(CMAKE_FIND_LIBRARY_SUFFIXES ".dll" ".dll.a" ".a")
 
 SET(CMAKE_C_CREATE_SHARED_MODULE
-  "<CMAKE_C_COMPILER> <CMAKE_SHARED_LIBRARY_C_FLAGS> <LINK_FLAGS> <CMAKE_SHARED_LIBRARY_CREATE_C_FLAGS> <CMAKE_SHARED_LIBRARY_SONAME_C_FLAG><TARGET_SONAME> -o <TARGET> <OBJECTS> <LINK_LIBRARIES>")
+  "<CMAKE_C_COMPILER> <CMAKE_SHARED_MODULE_C_FLAGS> <LINK_FLAGS> <CMAKE_SHARED_MODULE_CREATE_C_FLAGS> -o <TARGET> <OBJECTS> <LINK_LIBRARIES>")
 SET(CMAKE_CXX_CREATE_SHARED_MODULE
-  "<CMAKE_CXX_COMPILER> <CMAKE_SHARED_LIBRARY_CXX_FLAGS> <LINK_FLAGS> <CMAKE_SHARED_LIBRARY_CREATE_CXX_FLAGS> <CMAKE_SHARED_LIBRARY_SONAME_CXX_FLAG><TARGET_SONAME> -o <TARGET> <OBJECTS> <LINK_LIBRARIES>")
+  "<CMAKE_CXX_COMPILER> <CMAKE_SHARED_MODULE_CXX_FLAGS> <LINK_FLAGS> <CMAKE_SHARED_MODULE_CREATE_CXX_FLAGS> -o <TARGET> <OBJECTS> <LINK_LIBRARIES>")
 
 SET(CMAKE_C_CREATE_SHARED_LIBRARY
-  "<CMAKE_C_COMPILER> <CMAKE_SHARED_LIBRARY_C_FLAGS> <LINK_FLAGS> <CMAKE_SHARED_LIBRARY_CREATE_C_FLAGS> <CMAKE_SHARED_LIBRARY_SONAME_C_FLAG><TARGET_SONAME> -o <TARGET> -Wl,--out-implib,<TARGET_IMPLIB> <OBJECTS> <LINK_LIBRARIES>")
+  "<CMAKE_C_COMPILER> <CMAKE_SHARED_LIBRARY_C_FLAGS> <LINK_FLAGS> <CMAKE_SHARED_LIBRARY_CREATE_C_FLAGS> -o <TARGET> -Wl,--out-implib,<TARGET_IMPLIB> <OBJECTS> <LINK_LIBRARIES>")
 SET(CMAKE_CXX_CREATE_SHARED_LIBRARY
-  "<CMAKE_CXX_COMPILER> <CMAKE_SHARED_LIBRARY_CXX_FLAGS> <LINK_FLAGS> <CMAKE_SHARED_LIBRARY_CREATE_CXX_FLAGS> <CMAKE_SHARED_LIBRARY_SONAME_CXX_FLAG><TARGET_SONAME> -o <TARGET> -Wl,--out-implib,<TARGET_IMPLIB> <OBJECTS> <LINK_LIBRARIES>")
+  "<CMAKE_CXX_COMPILER> <CMAKE_SHARED_LIBRARY_CXX_FLAGS> <LINK_FLAGS> <CMAKE_SHARED_LIBRARY_CREATE_CXX_FLAGS> -o <TARGET> -Wl,--out-implib,<TARGET_IMPLIB> <OBJECTS> <LINK_LIBRARIES>")