docker clean up

Summary of changes

* moved code from shell script to RUN and ADD commands - better caching
* switched to *trusty* - upgrades primer3 to ```2.3.6```
* add asciidoc and ncurses as build requirements
* switch some apt-get ordering of installs
* switched to a test shell script to achieve more with no additional layers
  * usage of this is explained in script
* beagle installs as un-versioned filename - makes downstream agnostic to changes