as discussed at https://github.com/splitbrain/dokuwiki/pull/115

I hate using heights, but couldn't find any other way

Made sure all links align as well as possible in a list, giveing them
all the same padding.

Adjusted the template's icons to use 16x16 size and use the additional
space for alignment.

Adjusted some of the default interwiki icons (amazon, skype, paypal).

Template authors now can use tpl_sidebar() to include the sidebar.
Sidebars can be defined in subnamespaces as well

moved spacing corrections for first line away from h1 to .page in order to fix overlapping issue in Chrome (FS#2542)