Fix typos

Author: csswizardry

_posts/2017-02-12-base64-encoding-and-performance-part-2.md

@@ -195,7 +195,7 @@ requesting it, I was going to preload it:
 I didn’t notice any drastic improvements on this reduced test case because
 preload isn’t really useful here: I already have such a short request chain that
 we don’t get any real gains from reordering it. However, if we had a page with
-many assets, preload can certainly begin to give use some great boosts. I
+many assets, preload can certainly begin to give us some great boosts. I
 actually use it [on my homepage](/) to [preload the
 masthead](https://github.com/csswizardry/csswizardry.github.com/blob/21044ecec9e11998d7a1e12e9f96be2aa990c652/_includes/head.html#L5-L15):
 this is above the fold content that is normally quite late requested, so

_posts/2017-02-12-base64-encoding-and-performance.md

@@ -286,7 +286,7 @@ same rule. This means that if we change just one hex value in our CSS
 somewhere—a change that might represent up to six bytes of new data—we have to
 redownload hundreds of kilobytes of styles, images, and fonts.
 
-In fact, fonts are a really bad offender here: fonts and very, very unlikely to
+In fact, fonts are a really bad offender here: fonts are very, very unlikely to
 ever change. They’re a very infrequently modified resource. In fact, I just went
 and checked a long-running project that another client and I are working on: the
 last change to their CSS was yesterday; the last change to their font files was