Merge branch 'web-request'

Add wxWebViewRequest and related classes allowing to use HTTPS and
HTTP/2.

See https://github.com/wxWidgets/wxWidgets/pull/977

build/cmake/lib/net/CMakeLists.txt

@@ -25,6 +25,15 @@ wx_add_library(wxnet IS_BASE ${NET_FILES})
 
 if(WIN32)
     wx_lib_link_libraries(wxnet PRIVATE ws2_32)
+
+    if(wxUSE_WEBREQUEST_WINHTTP)
+        wx_lib_link_libraries(wxnet PRIVATE Winhttp)
+    endif()
+endif()
+
+if (wxUSE_WEBREQUEST_CURL)
+    target_include_directories(wxnet PRIVATE ${CURL_INCLUDE_DIRS})
+    wx_lib_link_libraries(wxnet PRIVATE ${CURL_LIBRARIES})
 endif()
 
 wx_finalize_lib(wxnet)