tracking julia fix: JuliaLang/julia@f38c2b8d0eff54efabc8c6a21f920aa71ddf399d
Merge pull request #331 from tanmaykm/master

tracking fix: JuliaLang/julia@f38c2b8d0eff54efabc8c6a21f920aa71ddf399d
Much faster writetable implementation
Revise I/O code
Update IO
Handle the empty string when quoted
Add the ability to modify a DF in place based on an I/O buffer
Fix deprecation of mege
Check for columns that are all NA's
Convert DataArray element type
Modify Describe function

1) Print out NA count/percentage for all cases. It feels more
comfortable to have NA always printed out explicitly, rather than
having to assume that NA = 0. Also, calculated NA% to give context
about data completeness

2) Added unique count for character string scenario, to help user
determine whether column should be pdv or if column is a key (i.e. high
cardinality column for joins, as opposed to factor)

3) Fixed formatting for character case to remove colons to match
numeric table format
Merge pull request #337 from randyzwitch/master

Modify Describe function
Update io.jl

I am not sure if I am catching what the original purpose of this if/else statement was but at least now I can correctly write out dataframes that have strings in them.
importing Base.Sort after JuliaLang/julia#3931
Merge pull request #340 from tanmaykm/master

importing Base.Sort after JuliaLang/julia#3931
Merge pull request #339 from dreiss-isb/patch-1

Update io.jl
Test that string columns print correctly
WIP: Distributed DataFrames and Blocks interface
update travis yml for Blocks
Merge pull request #344 from tanmaykm/ddataframe

WIP: Distributed DataFrames and Blocks interface