Lowercase section 1 title ala other sections

Update file name to reflect corrected title.

chapters/1-Introduction/1-1 Why Software Is Slow.md → chapters/1-Introduction/1-1 Why is software slow.md

@@ -1,4 +1,4 @@
-## Why Is Software Slow?
+## Why is software slow?
 
 If all the software in the world utilized all available hardware resources efficiently, then this book would not exist. We would not need any changes on the software side and would rely on what existing processors have to offer. But you already know that the reality is different, right? The reality is that modern software is *massively* inefficient. A regular server system in a public cloud typically runs poorly optimized code, consuming more power than it could have consumed (increasing carbon emissions and contributing to other environmental issues). If we could make all software run two times faster, we would potentially reduce the carbon footprint of computing by a factor of two.