Create resources/.gitignore file.

Create a .gitignore file in resources/ that is responsible for
preventing the downloaded binary files from being added to source control.

BUG=None
NOTRY=True

Review-Url: https://codereview.webrtc.org/2587163002
Cr-Commit-Position: refs/heads/master@{#15691}

resources/.gitignore

@@ -0,0 +1,21 @@
+**/*.aecdump
+**/*.bin
+**/*.byte
+**/*.chn
+**/*.dat
+**/*.frames
+**/*.gai
+**/*.jpg
+**/*.pb
+**/*.pcap
+**/*.pcm
+**/*.rtp
+**/*.rtpdump
+**/*.rx
+**/*.txt
+**/*.wav
+**/*.y4m
+**/*.yuv
+**/*.BIT*
+**/*.INP
+**/*.OUT*