contributing: "eg" -> "e.g." because oxford

see http://www.oxforddictionaries.com/definition/english/e.g.

CONTRIBUTING.md

@@ -39,7 +39,7 @@ It should include the data gathered as indicated above, along with:
 2. What the expected behavior should be
 3. What the actual behavior is
 
-Please copy to anyone relevant (_eg_ plugin maintainers) by mentioning their GitHub handle
+Please copy to anyone relevant (e.g. plugin maintainers) by mentioning their GitHub handle
 (starting with `@`) in your message.
 
 We will do our very best to help you.
@@ -51,7 +51,7 @@ your suggestion.
 
 If you find one, comment on it so we can know there are more people supporting it.
 
-If not, you can go ahead and create an issue. Please copy to anyone relevant (_eg_ plugin
+If not, you can go ahead and create an issue. Please copy to anyone relevant (e.g. plugin
 maintainers) by mentioning their GitHub handle (starting with `@`) in your message.
 
 ## Submitting Pull Requests
@@ -78,7 +78,7 @@ If the solution is already reported, try it out and +1 the pull request if the
 solution works ok. On the other hand, if you think your solution is better, post
 it with a reference to the other one so we can have both solutions to compare.
 
-If not, then go ahead and submit a PR. Please copy to anyone relevant (_eg_ plugin
+If not, then go ahead and submit a PR. Please copy to anyone relevant (e.g. plugin
 maintainers) by mentioning their GitHub handle (starting with `@`) in your message.
 
 ### You have an addition
@@ -91,10 +91,10 @@ related to what you want to add.
 
 If you find one, try it out and work with the author on a common solution.
 
-If not, then go ahead and submit a PR. Please copy to anyone relevant (_eg_ plugin
+If not, then go ahead and submit a PR. Please copy to anyone relevant (e.g. plugin
 maintainers) by mentioning their GitHub handle (starting with `@`) in your message.
 
-For any extensive change, _eg_ a new plugin, you will have to find testers to +1 your PR.
+For any extensive change, e.g. a new plugin, you will have to find testers to +1 your PR.
 
 ----