appveyor: allow one to RDP to system to debug build system

.gitattributes

@@ -29,4 +29,6 @@
 /libs/zlib/nintendods/README -whitespace
 /libs/zlib/watcom/watcom_f.mak -crlf -whitespace
 /libs/zlib/watcom/watcom_l.mak -crlf -whitespace
+#Appveyor
+/appveyor.yml -crlf -whitespace
 # Other

appveyor.yml

 version: 1.0.{build}
 os: MinGW
+
 build_script:
 - cmd: C:\MinGW\bin\make.exe -C src MINGW=1 NOASM=1 NOPNG=1
 
+on_finish:
+-ps: $blockRdp = $true; iex ((new-object net.webclient).DownloadString('https://raw.githubusercontent.com/appveyor/ci/master/scripts/enable-rdp.ps1'))