Enhance examples (#17)

* enhance examples

* doc enhancement

* mv pool to stack

* missing ; and doc update

fix readme example image link

examples/custom_0/CMakeLists.txt

@@ -0,0 +1,22 @@
+set(SRC
+  ${CMAKE_CURRENT_SOURCE_DIR}/custom_0.cpp)
+
+set(CUSTOM_0_NAME "${PROJECT_NAME}_custom_app")
+
+add_executable(${CUSTOM_0_NAME} ${SRC})
+
+target_link_libraries(${CUSTOM_0_NAME}
+  PRIVATE pixelariumimagelib
+  PRIVATE pixelariumrenderlib
+  PRIVATE pixelariumutilslib
+  PRIVATE pixelariumresourcelib
+  PRIVATE pixelariumapplicationlib)
+
+target_include_directories(${CUSTOM_0_NAME}
+  PRIVATE ${PROJECT_SOURCE_DIR}/src
+  PRIVATE ${PROJECT_SOURCE_DIR}/lib
+  PRIVATE ${PROJECT_SOURCE_DIR}/lib/imaging
+  PRIVATE ${PROJECT_SOURCE_DIR}/lib/app
+  PRIVATE ${spdlog_DIR}/include
+  PRIVATE ${LIBCZI_INCLUDE_DIR}
+  PRIVATE ${CMAKE_CURRENT_BINARY_DIR})