[file_system] moved copy/move tasks to own unit file.

Fixed issue at 'directory_enumerate_file_system_entries_wchar_t'
function:
if output encoding requested non UTF8, finish pointer do not refreshed
to up-to-date data and fail return may provided in same case where with
UTF8 output encoding function return success.

[interpreter] at 'interpreter_get_value_for_argument' function make sure
that returned empty string is really means empty and code that provided
such do not requested to be added as function return value.
In this case for some of test cases from the tests.xml requested
addition changes. At the string::empty function actually script code
used as input, that actually mean - empty value.
For some reason get-host-name may not set at some environments so that
test case also upgraded.

[copy_move] changed signature of 'copy_evaluate_task' and
'move_evaluate_task' functions. Only cases with different input and
output encodings and that used nested elements of copy and move tasks
not covered.

[tests.xml] at 'loadfile sample' removed expected to use code - at other
tests used such for, here left unchanged use property::get-value
function to cover last one too.

[tests_project] expected base directory from test environment is
interpreting before compare to returned value.

CMakeLists.txt

@@ -17,6 +17,8 @@ add_library(ant4c STATIC
             "${CMAKE_SOURCE_DIR}/common.h"
             "${CMAKE_SOURCE_DIR}/conversion.c"
             "${CMAKE_SOURCE_DIR}/conversion.h"
+            "${CMAKE_SOURCE_DIR}/copy_move.c"
+            "${CMAKE_SOURCE_DIR}/copy_move.h"
             "${CMAKE_SOURCE_DIR}/date_time.c"
             "${CMAKE_SOURCE_DIR}/date_time.h"
             "${CMAKE_SOURCE_DIR}/echo.c"
@@ -69,20 +71,26 @@ add_library(ant4c STATIC
 add_executable(ant4c_app
             "${CMAKE_SOURCE_DIR}/main.c")
 
+# add_library(ant4c_lib SHARED
+#             "${CMAKE_SOURCE_DIR}/main.c")
+
 #if (MSVC OR MINGW)
 #  add_compile_definitions(ant4c UNICODE _UNICODE)
 #  add_compile_definitions(ant4c_app UNICODE _UNICODE)
 #endif()
 
 target_link_libraries(ant4c_app ant4c)
+# target_link_libraries(ant4c_lib ant4c)
 
 if(DEFINED PROGRAM_VERSION)
   target_compile_definitions(ant4c PRIVATE -DPROGRAM_VERSION=${PROGRAM_VERSION})
   target_compile_definitions(ant4c_app PRIVATE -DPROGRAM_VERSION=${PROGRAM_VERSION})
+  # target_compile_definitions(ant4c_lib PRIVATE -DPROGRAM_VERSION=${PROGRAM_VERSION})
 endif()
 
 if(NOT MSVC)
   target_link_libraries(ant4c_app m)
+  # target_link_libraries(ant4c_lib m)
 endif()
 
 set(SOURCES_OF_EXEC_APP "${CMAKE_SOURCE_DIR}/tests_exec_app.c")