Changes the email address specified in the gemspec file.

minesweeper.gemspec

@@ -7,7 +7,7 @@ Gem::Specification.new do |spec|
   spec.name          = "minesweeper"
   spec.version       = Minesweeper::VERSION
   spec.authors       = ["Sebastien Varlet"]
-  spec.email         = ["sebastien.varlet@plumbee.co.uk"]
+  spec.email         = ["sebastien.varlet@gmail.com"]
   spec.summary       = %q{Core model of the minesweeper game.}
   spec.description   = %q{This gem defines the core classes of a minesweeper game such as Minefield, Cell, and Mine.}
   spec.homepage      = "https://github.com/svarlet/minesweeper"