bump to alpine 3.6

Update to tvheadend 4.2.1 stable

use repo version of gnu-libiconv rather than compile it

use one block and --installdeps for cpanm packages

change order of perl cpan package installs

Perl changes, add picons file to gitignore and update XMLTV to 0.5.69

Add variable to add additional runtime paramters

Update Alpine to 3.5, change dvb-apps to only compile needed libs and update README.

Add picons to /picons and add info to README