To support yocto on systems with python3 as default version, scripts
should use /usr/bin/env python in the shebang, as this allows the use of
a fake env to mimic python2 as default version.

This patch simply replaces occurrences of #!/usr/bin/python with
 #!/usr/bin/env python and was done with this oneliner:

     git grep -lE '^#!/usr/bin/python' | xargs \
         sed -i 's|/usr/bin/python|/usr/bin/env python|'

(From OE-Core rev: 6d3de22a19657a413e01d7bb5fd74d16c00dc696)

Signed-off-by: Martin Hundebøll <martin@hundeboll.net>
Signed-off-by: Ross Burton <ross.burton@intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
Signed-off-by: Armin Kuster <akuster808@gmail.com>

The first iterations of wic very shortsightedly catered to two
specific use-cases and added special-purpose params for those cases so
that they could be directly given their corresponding boot artifacts.
(hdddir and staging_data_dir).

As more use-cases are added, it becomes rather obvious that such a
scheme doens't scale, and additionally causes confusion for plugin
writers.

This removes those special cases and states explicitly in the help
text that plugins are responsible for locating their own boot
artifacts.

(From OE-Core rev: 6ba3eb5ff7c47aee6b3419fb3a348a634fe74ac9)

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
Signed-off-by: Armin Kuster <akuster808@gmail.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

As well as any other stray instances of mic in the codebase that can
be removed.

We don't really need to carry around legacy naming, and the history is
in git.

Signed-off-by: Tom Zanussi <tom.zanussi@linux.intel.com>