Update pattern for chcp_encoding detection for PowerShellRepl

I got the error "Can't detect encoding from chcp" on my Win7 64bit German
  C:\Dropbox\c\my> chcp 65001
  Aktive Codepage: 65001.
RegEx Pattern was changed to capture this
Merge pull request #163 from fbehrens/patch-1

Update pattern for chcp_encoding detection for PowerShellRepl