cmake: another guess at what appveyor needs

Call runtest via perl to make it easier on Windows

regress/CMakeLists.txt

diff --git a/regress/CMakeLists.txt b/regress/CMakeLists.txt
index af0d7da..da4fd1e 100644
--- a/regress/CMakeLists.txt
+++ b/regress/CMakeLists.txt
@@ -151,7 +151,8 @@
   TARGET_LINK_LIBRARIES(${PROGRAM} zip)
 ENDFOREACH(PROGRAM ${GETOPT_USERS})
 
-SET(CMAKE_MSVCIDE_RUN_PATH ${CMAKE_BINARY_DIR}/lib;$ENV{CMAKE_PREFIX_PATH}/bin)
+# for appveyor builds
+SET(CMAKE_MSVCIDE_RUN_PATH C:\projects\libzip\vstudio\zlib\installed\lib;${CMAKE_BINARY_DIR}/lib/Release)
 
 ADD_CUSTOM_TARGET(
   testinput ALL
@@ -178,7 +179,7 @@
 )
 
 FOREACH(CASE ${EXTRA_TESTS})
-  ADD_TEST(${CASE} ${CMAKE_BINARY_DIR}/regress/runtest ${CMAKE_CURRENT_SOURCE_DIR}/${CASE})
+  ADD_TEST(${CASE} perl ${CMAKE_BINARY_DIR}/regress/runtest ${CMAKE_CURRENT_SOURCE_DIR}/${CASE})
 ENDFOREACH(CASE ${EXTRA_TESTS})
 
 INCLUDE_DIRECTORIES(${CMAKE_CURRENT_SOURCE_DIR}/../lib