Cannot install package

[Marcus Baffa]

               _

   _       _ _(_)_     |  A fresh approach to technical computing

  (_)     | (_) (_)    |  Documentation: http://docs.julialang.org

   _ _   _| |_  __ _   |  Type "?help" for help.

  | | | | | | |/ _` |  |

  | | |_| | | | (_| |  |  Version 0.4.3 (2016-01-12 21:37 UTC)

 _/ |\__'_|_|_|\__'_|  |  Official http://julialang.org/ release

|__/                   |  x86_64-w64-mingw32

julia> Pkg.add("Jewel")

fatal: Not a git repository (or any of the parent directories): .git

ERROR: failed process: Process(setenv(`git rev-parse --git-dir`; dir="C:\\Users\\mbaffa\\.julia\\v0.4\\METADATA"), ProcessExited(128)) [128]

 in pipeline_error at process.jl:555

julia>