This is mainly a clean up patchset. It moves the WebM writing support
out of vpxenc and into its own source file. Changes to tools_common and
vpxdec result from relocation of shared bits of code.
Change-Id: Iee55d3285f56e0a548f791094fb14c5ac5346a26
STDIO streams are opened in text mode by default on Windows. This patch
changes the stdin/stdout streams to be in binary mode if they are being
used for I/O from the vpxenc or vpxdec tools.
Fixes issue #216. Thanks to mw AT hesotech.de for the fix.
Change-Id: I34525b3ce2a4a031d5a48d36df4667589372225b