Modified assemble module so the dest file is streamed together rather than built-in memory before writing.

 - added terse syntax to modules.rst
 - added description of special variables to template module

  plus a small fix in rst.j2 template
  manpages generated & checked
  modules.html generated & checked

whitespace + remove deprecated YAML parser (migration script lives in examples/scripts and warning was added
in 0.6 release)

Add encoding lines to python modules such that they can take unicode options if they are fed them, since the
AnsibleModule stuff no longer base64 encodes for simplicity and speed reasons.

This reverts commit 865796c3687cc06920ddf29890de991287dc50f6.

(Superseeded by next commit)

Import hashlib if it is there, otherwise import md5.  Adds method
file_digest that wraps the logic on which module to invoke.

This adds a module that concatenates (ie. assembles) a file from
fragments in a directory in alphabetical order.  It chains the file
module afterward to fix up ownership and permission.  This also adds
tests for the assemble module with fragments in assemble.d.