log a bit more and var_prompts

file module: mode formatting & directory ownership

improvements to apt module

support for 'link' state in file module

Remove shebang from callbacks.py

raise error if executable host file execution fails

bugfix for extra-vars

- this allows some vars to be prompted for at the start of the playbook
  setup
- defaults to no output since this would mostly be used for passwords

It is not +x, and has no __main__.  It draws ire of rpmlint.

yum module fix - catch more errors

catch all exceptions and emit sensible errors - if we have a config file error this lets us know about it

Eliminate possible race condition in async_wrapper where ansible deletes the argsfile while the module
is still kicking off.  Should not happen except in modules that are somewhat slow to load and probably
can be fixed better than the included sleep, i.e. some IPC communication that the process has
launched and is ok to exit.  This works pretty well for now though.

Run tests in verbose mode.

Stderr logging

Make copy module idempotent.

Check md5sum before overwriting a file. Unconditionally copying changes the timestamp.

Correct default user and port in playbook.

d would be useful for --dry-run.

This prints remote module stderr on local stderr.

This prints the stderr of the executed modules on local stderr.
Most methods on Runner now return a fourth "err" parameter.

They are set in the constructor.