dispatch: don't mangle ImportError abort messages Previously, Mercurial assumed that the last word of the string representation was the name of the moduled that was imported. This assmption is incorrect, despite being true for the common case of an exception raised by the Python VM. For example, hgsubversion raises an ImportError with a helpful message if the Subversion bindings were not found. The final word of this message is not meaningful on its own, and is never the name of a module. This patch changes the output printed to be a simple stringification of the exception instance. In most cases, this will be `abort: No module named X!' rather than `abort: could not import module X!'. No functionality change; all tests pass.