add parentheses to remove the ambiguity on Elixir 1.4

[alexandrubagu]

When using Elixir 1.4 new warnings are raised:

warning: variable "erlc_options" does not exist and is being expanded to "erlc_options()", please use parentheses to remove the ambiguity or change the variable name
  /home/alexandrubagu/devel/antidote/deps/jose/mix.exs:8

warning: variable "deps" does not exist and is being expanded to "deps()", please use parentheses to remove the ambiguity or change the variable name
  /home/alexandrubagu/devel/antidote/deps/jose/mix.exs:11

warning: variable "description" does not exist and is being expanded to "description()", please use parentheses to remove the ambiguity or change the variable name
  /home/alexandrubagu/devel/antidote/deps/jose/mix.exs:19

warning: variable "package" does not exist and is being expanded to "package()", please use parentheses to remove the ambiguity or change the variable name
  /home/alexandrubagu/devel/antidote/deps/jose/mix.exs:20

[potatosalad]

@alexandrubagu Awesome, thanks!

[alexandrubagu]

Can you create a new tag with this ? There are libraries which still use 1.8 tag and are warnings when you compile

[potatosalad]

@alexandrubagu Just published version 1.8.1 with your changes included. Thanks!

[alexandrubagu]

Thanks a lot