Readme referenced no-longer existing variable

How the lighter is created has apparently changed, but the readme was
never updated.
Merge pull request #414 from tanzoniteblack/update-readme-lighter

Readme referenced no-longer existing variable
Added support for SCons projects
Merge pull request #417 from npcardoso/master

Added support for SCons projects
Add new command "projectile-find-other-file"

This command is used for switching between files with the same name but
with different extensions in the current project. It would be useful for
switching between header files and source files in C/C++, an possibly
test files with the same names.
Merge pull request #421 from tuhdo/master

Add new command "projectile-find-other-file"
[Fix #412] Handle multiple possible targets in projectile-toggle-between-implementation-or-test
Handle Objective-C extensions in projectile-find-other-file