Unconfigured git error
Git repository might be created but git might be not configured.
The results of this failure:
1. .gitignore file was not created.
2. change was not committed

```
c:\\src\\tmp>dvc init
Directories data/, .cache/ and .state/ were created
Error. Git command error (git commit -m DVC init. data dir data, cache dir .cache, state dir .state):
*** Please tell me who you are.

Run

  git config --global user.email "you@example.com"
  git config --global user.name "Your Name"

to set your account's default identity.
Omit --global to set the identity only in this repository.

fatal: empty ident name (for <(NULL)>) not allowed
```
diff --git a/dvc/git_wrapper.py b/dvc/git_wrapper.py
index f466db785..4cc5d5e32 100644
--- a/dvc/git_wrapper.py
+++ b/dvc/git_wrapper.py
@@ -46,6 +46,15 @@ class GitWrapperI(object):
 
         return GitWrapper.parse_porcelain_files(out)
 
+    @staticmethod
+    def git_config_get(name):
+        code, out, err = Executor.exec_cmd(['git', 'config', '--get', name])
+        Logger.debug('[dvc-git] "git config --get {}": code({}), out({}), err({})'.format(
+                                                               name, code, out, err))
+        if code != 0:
+            return None
+        return out
+
     @staticmethod
     def git_path_to_system_path(path):
         if os.name == 'nt':
@@ -86,6 +95,17 @@ class GitWrapper(GitWrapperI):
                 Logger.error("{} {}".format(status, file))
             return False
 
+        # Sanity check to make sure we will be able to commit
+        name = self.git_config_get('user.name')
+        if name == None:
+            Logger.error('[dvc-git] Please setup user.name in git config')
+            return False
+
+        email = self.git_config_get('user.email')
+        if email == None:
+            Logger.error('[dvc-git] Please setup user.email in git config')
+            return False
+
         return True
 
     @property
['dvc/git_wrapper.py']