Don't use bash shopt in the wrapper script

Some images with a bash shell don't support the "shopt" command used in the wrapper script, so it should be removed to make the generated scripts more portable. Some default devstack images don't support the command (see [1]), so fixing this may help significantly testing jclouds with openstack.

The used at the moment are:

• xpg_echo: Turns on/off the interpretation of the backslash (to interpret or not the '\n', for example).
• expand_aliases: Turns on/off the alias expanding. This allows to define alias in the script and use them later.

The first one can be removed, if all calls to the "echo" command that need to interpret the backslash are changed to "echo -e".
The second one, could be removed if the alias definitions are replaced by bash functions, which should be a direct change.

[1] http://apache.markmail.org/thread/n4dna3rmapcj42o3