Updated changelog to fix a few minor spelling issues

I was just searching through the changelog for a few things and saw something wasn't being highlighted, and realized it was because of a minor spelling mistake.  I then took the time to do a bit more spelling error cleanup just in case someone else runs into the problem I did.

Author: scouttyg

CHANGELOG.md

@@ -42,12 +42,12 @@
 2.2.13
 ------
 
-* Several peformance optimizations: [#260](https://github.com/rails/jbuilder/pull/260) & [#261](https://github.com/rails/jbuilder/pull/261)
+* Several performance optimizations: [#260](https://github.com/rails/jbuilder/pull/260) & [#261](https://github.com/rails/jbuilder/pull/261)
 
 2.2.12
 ------
 
-* [Replace explici block calls with yield for performance](https://github.com/rails/jbuilder/commit/3184f941276ad03a071cf977133d1a32302afa47)
+* [Replace explicit block calls with yield for performance](https://github.com/rails/jbuilder/commit/3184f941276ad03a071cf977133d1a32302afa47)
 
 2.2.11
 ------
@@ -191,7 +191,7 @@
 -----
 * [Add quick collection attribute extraction](https://github.com/rails/jbuilder/commit/c2b966cf653ea4264fbb008b8cc6ce5359ebe40a)
 * [Block has priority over attributes extraction](https://github.com/rails/jbuilder/commit/77c24766362c02769d81dac000b1879a9e4d4a00)
-* [Meaningfull error messages when adding properties to null](https://github.com/rails/jbuilder/commit/e26764602e34b3772e57e730763d512e59489e3b)
+* [Meaningful error messages when adding properties to null](https://github.com/rails/jbuilder/commit/e26764602e34b3772e57e730763d512e59489e3b)
 * [Do not enforce template format, enforce handlers instead](https://github.com/rails/jbuilder/commit/72576755224b15da45e50cbea877679800ab1398)
 
 1.3.0