examples : add "simple" (#1840)

* Create `simple.cpp`

* minimalist example `CMakeLists.txt`

* Update Makefile for minimalist example

* remove 273: Trailing whitespace

* removed trailing white spaces simple.cpp

* typo and comments simple.cpp

---------

Co-authored-by: Georgi Gerganov <ggerganov@gmail.com>

examples/simple/CMakeLists.txt

@@ -0,0 +1,7 @@
+set(TARGET simple)
+add_executable(${TARGET} simple.cpp)
+target_link_libraries(${TARGET} PRIVATE common llama ${CMAKE_THREAD_LIBS_INIT})
+target_compile_features(${TARGET} PRIVATE cxx_std_11)
+if(TARGET BUILD_INFO)
+  add_dependencies(${TARGET} BUILD_INFO)
+endif()