Fix start.sh
Fix start.sh

Lots of little problems:
- gnome-terminal was complaining about some config option hidden somewhere.
Replaced with much-more-common 'xterm'.
- AppEngine wanted to see --skip_sdk_update_check with explicit =true argument
- Added support for running on MacOS.
	Change on 2015/02/23 by mgainer <mgainer@google.com>
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=87009892

andela-angene/coursebuilder-core,andela-angene/coursebuilder-core,andela-angene/coursebuilder-core,andela-angene/coursebuilder-core