Minor formatting fixes for data.txt.
Adding Learnist (formerly known as Grockit).

Contributor: Anonymous
Source: recruiters working for the company

'According to a recruiter for Learnist named Josh Ueberroth, there are
"25 Ruby Engineers, iOS and Android Developers". According to another
recruiter for the same company, Clara Ma, they just hired their first
female engineer, an iOS developer.'
Adding Hipmunk.

Contributor: Christopher Beacham, christopher@hipmunk.com
Source: internal headcount
Adding Levo.

Contributor: Sophia Chou, Chief Product Officer at Levo.com, @sophiachou
Source: internal headcount

https://github.com/triketora/women-in-software-eng/pull/12
Allow update_script.py to take a spreadsheet key param.