README: Fixes.

README.md

@@ -10,7 +10,7 @@ functions more comfortable in Typed Racket.
 This package is distributed under the [GNU GPLv3
 licence](https://www.gnu.org/licenses/quick-guide-gplv3.html).
 
-# Contributing
+## Contributing
 
 Contributions, comments, bug reports, etc. are very welcome!
 
@@ -18,11 +18,11 @@ For [ethical
 reasons](https://en.wikipedia.org/wiki/Embrace,_extend,_and_extinguish),
 I prefer not to host this package on
 [GitHub](https://en.wikipedia.org/wiki/GitHub#Acquisition_by_Microsoft).
-Luckily, Git allows creating and submitting patches by E-mail in very
+Luckily, Git allows creating and submitting patches by E-mail very
 easily.  Here is a simple workflow that you can use to contribute to
 this library.
 
-## Submit patches
+### Submitting patches
 
 Start by checking out this repository:
 
@@ -60,9 +60,9 @@ saying that I will probably take in your changes without too much
 hassle if they follow some very basic style guidelines.  Speaking of
 which:
 
-## Style guidelines
+### Style guidelines
 
-When submitting changes, try to make it as similar as possible in
+When submitting changes, try to make them as similar as possible in
 style to the existing code, which approximately follows the style used
 across the Racket code base. If you use Emacs with Racket Mode or
 DrRacket, you should be fine with default settings.