Fix failure to correctly detect Apache Portable Runtime (APR).

This resolves bug report 916.
Thanks to David C. Rankin.

ConfigureChecks.cmake

@@ -119,6 +119,12 @@ IF (UNIX)
   endif(NOT APU_CONFIG)
 
   EXEC_PROGRAM(${APR_CONFIG} ARGS "--includedir" OUTPUT_VARIABLE APR_INCLUDE_DIR_INT)
+
+  pkg_search_module( APR apr-1 )
+  if( NOT APR_FOUND )
+    tde_message_fatal( "apr-1 is required, but was not found on your system" )
+  endif( )
+
   EXEC_PROGRAM(${APU_CONFIG} ARGS "--includedir" OUTPUT_VARIABLE APU_INCLUDE_DIR_INT)
   SET(APR_INCLUDE_DIR "${APR_INCLUDE_DIR_INT}" CACHE INTERNAL "")
   SET(APU_INCLUDE_DIR "${APU_INCLUDE_DIR_INT}" CACHE INTERNAL "")

src/CMakeLists.txt

@@ -25,7 +25,7 @@ include_directories(
   ${CMAKE_SOURCE_DIR}/src/svnfrontend
   ${CMAKE_SOURCE_DIR}/src/svnqt/cache
   ${SUBVERSION_INCLUDE_DIR}
-  /usr/include/apr-1.0
+  ${APR_INCLUDE_DIRS}
 )
 
 link_directories(