getConfigEnv fails fast when key is not found and no default value is given.
Summary:
T2345
getConfig throws an Exception when the key does not exist.
Also removes dead code that throws an Exception.
Test Plan:
Reloaded the Phabricator home page. In the process, found
2 Exceptions thrown due to nonexistent keys. After addressing these problems,
the home page loads without Exceptions.
Reviewers: epriestley
Reviewed By: epriestley
CC: aran, Korvin
Differential Revision: https://secure.phabricator.com/D4541