Fix typos

Author: tbroadley

CONTRIBUTING.md

@@ -5,7 +5,7 @@ Contribution Guidelines
 
 We try to be available pretty often to help when problems come up. We like to split incoming questions
 into two categories: potential bugs/features, and questions. If you want a feature added, or think you've found a bug
-in the code (or in the examples), search the [issue tracker](https://github.com/nodegit/nodegit/issues) and if you dont
+in the code (or in the examples), search the [issue tracker](https://github.com/nodegit/nodegit/issues) and if you don't
 find anything, file a new issue. If you just have questions, instead of using issues, [sign up](http://slack.libgit2.org/)
 to libgit2's Slack instance and then contact us in the [#nodegit channel](https://libgit2.slack.com/messages/nodegit/).
 

guides/install/from-source/README.md

@@ -76,7 +76,7 @@ See here for more details:
 
 ### <a name="debug-build"></a>Debug build: ###
 
-In order to track down possible bugs, you will need a debug buid so you
+In order to track down possible bugs, you will need a debug build so you
 can get a backtrace with [gdb](http://www.gnu.org/software/gdb/) or
 [lldb](http://lldb.llvm.org/).