extract some basic code from libcryptonote_core into libcryptonote_basic

contrib/epee/src/CMakeLists.txt

@@ -27,6 +27,7 @@
 # THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
 add_library(epee STATIC http_auth.cpp mlog.cpp)
+
 # Build and install libepee if we're building for GUI
 if (BUILD_GUI_DEPS)
     if(IOS)
@@ -36,4 +37,11 @@ if (BUILD_GUI_DEPS)
     endif()
     install(TARGETS epee
         ARCHIVE DESTINATION ${lib_folder})
-endif()
+endif()
+
+target_link_libraries(epee
+  PUBLIC
+    crypto
+    ${Boost_FILESYSTEM_LIBRARY}
+  PRIVATE
+    ${EXTRA_LIBRARIES})