Don't print a warning when starting the server outside a Git repo

Currently, git checks are performed on server start, even when outside a git
repository.

This commit verify the presence of a git repository (via `git status` exit
code), and perform checks only if it exists.

closes #7712

Changelog.md

@@ -1,6 +1,7 @@
 # 0.7.4.0
 
 ## Refactor
+* Don't print a warning when starting the server outside a Git repo [#7712](https://github.com/diaspora/diaspora/pull/7712)
 
 ## Bug fixes
 

script/server

@@ -63,6 +63,9 @@ fi
 
 command -v git > /dev/null 2>&1
 if [ $? -eq 0 ]; then
+  # Check if we're in a repository, before doing any verification.
+  if git status > /dev/null 2>&1;
+  then
     # Check if git merge is in progress
     if [ -f .git/MERGE_MODE ]; then
       fatal "A git merge is in progress!"
@@ -74,6 +77,7 @@ if [ $? -eq 0 ]; then
     then
       warning "You are in detached HEAD state!"
     fi
+  fi
 fi
 
 # Do RVM checks if RVM is being used