added first tutorial
from the sotkanet packge vignette
and added new template in layouts for tutorial pages
feel free to change anything, just getting this up as a first shot
Fix typo in tutorial Front Matter
Move tutorial images to 'figs' folder

Using '_assets' won't work because files will not be copied to
'_site' unless they are referenced to somewhere.
Dedicated knit*.R scripts

Separate scripts for knitting Rmd posts and tutorial
vignettes.
Remake sotkanet tutorial
Add Rake task for automatically building tutorials
Add Rubyzip to Gemfile
Add TravisCI config
Test TravisCI
Add exit status 1 to Rakefile
Fix travis on branch
Add Rstudio CRAN mirror to rake
Restrict email notifications
Add knitr to travis
Add knitr to travis
Add table_print to Gemfile
Rakfile now lists available tutorials
Update rake task in travis
Update rake task in travis
Rename package_page to tutorial_page