Fix typos:
  `funciton` | `function`
  `calcuation` | `calculation`
  `spliting` | `splitting`
  `opertor` | `operator`
  `separted` | `separated`
  `sucessfully` | `successfully`
  `Oudented` | `Outdented`
  `Oparator` | `Operator`
  `simplifed` | `simplified`
  `ourselfs` | `ourselves`
  `documenation` | `documentation`
  `excetion` | `exception`
  `mutliple` | `multiple`
  `curent` | `current`
  `mutiple` | `multiple`
diff --git a/CHANGELOG b/CHANGELOG
index 16ad1e2..7e91453 100644
--- a/CHANGELOG
+++ b/CHANGELOG
@@ -12,7 +12,7 @@
 - use_tabs=True always uses a single tab per indentation level; spaces are
   used for aligning vertically after that.
 - Relax the split of a paren at the end of an if statement. With
-  `dedent_closing_brackets` option requires that it be able to split there. 
+  `dedent_closing_brackets` option requires that it be able to split there.
 
 ## [0.20.0] 2017-11-14
 ### Added
@@ -95,7 +95,7 @@
 
 ## [0.16.3] 2017-07-13
 ### Changed
-- Add filename information to a ParseError excetion.
+- Add filename information to a ParseError exception.
 ### Fixed
 - A token that ends in a continuation marker may have more than one newline in
   it, thus changing its "lineno" value. This can happen if multiple
@@ -180,7 +180,7 @@
 ## [0.15.0] 2017-01-12
 ### Added
 - Keep type annotations intact as much as possible. Don't try to split the over
-  mutliple lines.
+  multiple lines.
 ### Fixed
 - When determining if each element in a dictionary can fit on a single line, we
   are skipping dictionary entries. However, we need to ignore comments in our