2.5.1+g2444e2e409

Add -utf8 option to force UTF8 encoding

Attempt to fix #146. The console host and shell's output encoding still play a major factor, however. In cmd.exe, you still need to set chcp to display strings. In powershell.exe, you need to set chcp to display strings and use [Console]::OutputEncoding = 'UTF8' when redirecting to a file (which will itself encode as Unicode). The -utf8 switch does, however, fix the problem in testing with Node's child_process.execFile.