Merge pull request #28 from Gimperion/master

add Ubuntu easy install method
move/add vw links
add stemming with nltk
make twitter search string more obvious
add vw tutorial link
add concrete vw example
clean out detritus
add optional vw assignment
add link to fastML vw on adzuna post
take out breaking of output file
add questions etc.
some more words on vw
kitchen sink vw links
rename 12
add usage
re-order things and clean up
remove stub
swap dim_reduc and clustering
re-org lemons
cleaning, moving python intro stuff