added lens install instructions from README
typo in tar file extension
fixed #! to /bin/bash
install lens before_install
cd back to project directory
if there is a config file source it for LENSDIR

otherwise the LENSDIR will be ~/code/Lens
removed reduundent export command
exports now depend on if there is a config file
lens install config file for travis
export proj dir to cd to after lens install
added newline at eof
Merge pull request #47 from chendaniely/feature-lens-install-script

Feature lens install script