Clean up cmake files (Part 1)

I've been cleaning up the way compilation flags are passed to the targets
and there are still some changes that must be made, in the next commit.

I've also done some renaming, all_programs into programs and the same for
tests.

The gdb initialization file now is just one, populated using the find command
and using realpath to get the absolute path to the files. I've tested if the
generated gdb.run file works and it does.

programs/tests/CMakeLists.txt

@@ -56,7 +56,7 @@ endif(CMAKE_BUILD_TYPE STREQUAL "Debug")
 # BUILD
 # =============================================================================
 # Add your file in this list.
-set(TESTS
+set(TEST_LIST
     t_gid.c
     t_alarm.c
     t_periodic3.c
@@ -91,7 +91,7 @@ set(TESTS
 # Set the directory where the compiled binaries will be placed.
 set(MENTOS_TESTS_DIR ${CMAKE_SOURCE_DIR}/files/bin/tests)
 
-foreach(FILE_NAME ${TESTS})
+foreach(FILE_NAME ${TEST_LIST})
     # Prepare the program name.
     string(REPLACE ".c" "" EXECUTABLE_NAME ${FILE_NAME})
     
@@ -131,8 +131,8 @@ foreach(FILE_NAME ${TESTS})
     set_target_properties(${TARGET_NAME} PROPERTIES OUTPUT_NAME "${EXECUTABLE_NAME}")
 
     # Append the program name to the list of all the executables.
-    list(APPEND ALL_TESTS ${TARGET_NAME})
+    list(APPEND ALL_EXECUTABLES ${TARGET_NAME})
 endforeach()
 
 # Add the overall target that builds all the programs.
-add_custom_target(all_tests ALL DEPENDS ${ALL_TESTS})
+add_custom_target(tests ALL DEPENDS ${ALL_EXECUTABLES})