add json resource functions
resource chunks supports *.csv

Fixes #738
add json examples
json gzip
curried implementation for into

    >>> f = into(list)
    >>> f((1, 2, 3))
    [1, 2, 3]
rename Table to Data
move table.py to interactive.py
dplyr uses Symbol rather than TableSymbol
TableSymbol -> symbol in compute
simplify mongo pytest fixtures, lower to values

OK with this sort of change @cpcloud?
remove interactive elements from compute
update docs to Table -> Data switch
Field print itself as t.x rather than t['x']
json gzip uses gzip.open(mode='rt')
Merge branch 'master' into json
Merge branch 'master' into into-curry

Conflicts:
	blaze/api/into.py
Merge pull request #746 from mrocklin/json

Json resource functions
Merge pull request #752 from mrocklin/into-curry

curried implementation for into
fix import in api.__init__ for interactive <- table
use t.x instead of t['x'] in docs