Provide a default output encoding

Set a class attribute on the App to force the input/output
encoding in case neither stdout nor getdefaultencoding() have
a valid value. This case comes up sometimes under test runners
that capture stdout, without setting up a proper encoding
for the stream capture buffer.

Change-Id: Iab1d0b1549e1d00f64ef36765852261c108e0388
force python2.6 for that test env

Change-Id: I3aa10ae666c5806048145b7640e705bc5fca16ea
prepare for 1.4.3 release

Change-Id: I4c7c7dd27ac5e0ee98089e5be892df7759cba377