Regenerate READMEs

exercises/etl/README.md

-# Etl
+# ETL
 
 We are going to do the `Transform` step of an Extract-Transform-Load.
 

exercises/ocr-numbers/README.md

-# Ocr Numbers
+# OCR Numbers
 
 Given a 3 x 4 grid of pipes, underscores, and spaces, determine which number is
 represented, or whether it is garbled.

exercises/pascals-triangle/README.md

-# Pascals Triangle
+# Pascal's Triangle
 
 Compute Pascal's triangle up to a given number of rows.
 

exercises/rna-transcription/README.md

-# Rna Transcription
+# RNA Transcription
 
 Given a DNA strand, return its RNA complement (per RNA transcription).