Updates Smart Contract For Better Flow

I added the `posts.length` to `numPosts()` because it does not appear in the instructions and removed 2 `return` statements that I know will confuse people if left in, based on experience with a similar set up for the one function from DTwitter in India.

contracts/DReddit.sol

@@ -35,8 +35,7 @@ contract DReddit {
         view
         returns(uint)
     { 
-        // TODO: 
-        return 1;
+        return posts.length;
     }
 
     // @notice Create Post
@@ -65,7 +64,6 @@ contract DReddit {
         returns (bool)
     {
         // TODO:
-        return true;
     }
 
     // @notice Obtain vote for specific post
@@ -77,7 +75,6 @@ contract DReddit {
         returns (uint8)
     {
         // TODO:
-        return 1;
     }
 
 }