bug fixed in outline-demote and outline-promote.

 optional arg could be nil, but was supposed to be a number-or-marker later in
the chain of functions called to change the headline level.
total refactoring of menus and key-bindings. bug fixed in
'outline-move-subtree-up' and 'outline-move-subtree-down'.
comment-cruft removed
tiny change
optional imenu support for outshine headlines implemented.
temporary (and only partly) solution to problem wrt keybindings shown in
outshine menu.
enhanced support for imenu/idomenu added.
outshine-imenu introduced as convenience function for calling imenu/idomenu
from outshine.

Makes sure that imenu-generic-expression is set accordingly and buffer is
rescanned after each search.
'interactive function for `outshine-imenu' improved.
displaying whole match as default case in keyword-search with imenu/idomenu.
regexp for imenu keyword searches fixed (back to old state).

TODO: deal with eol.
comment string of `outshine-imenu-with-navi-regexp' updated.
Least possible changes for package.el compatibility
Merge pull request #13 from purcell/patch-1

Least possible changes for package.el compatibility
Headline-style converted back to old-school.

To confirm to the formatting requirements of package.el - and be able to add
outshine.el to MELPA - headlines were converted from 'org-style' to
'oldschool' and a few additional lines added.
Fix minor spelling.

Fix the spelling of 'detailed' in the README.
Merge pull request #14 from TrevorS/patch-1

Fix minor spelling.