Update API documentation (#330)

README.md

@@ -27,6 +27,12 @@ Significant diversions are expected to occur in the future such as streaming, EB
 
 ### `babylon.parse(code, [options])`
 
+### `babylon.parseExpression(code, [options])`
+
+`parse()` parses the provided `code` as an entire ECMAScript program, while
+`parseExpression()` tries to parse a single Expression with performance in
+mind. When in doubt, use `.parse()`.
+
 ### Options
 
 - **allowImportExportEverywhere**: By default, `import` and `export`
@@ -37,7 +43,7 @@ Significant diversions are expected to occur in the future such as streaming, EB
   the top level raises an error. Set this to `true` to accept such
   code.
 
-- **allowSuperOutsideMethod** TODO
+- **allowSuperOutsideMethod**: TODO
 
 - **sourceType**: Indicate the mode the code should be parsed in. Can be
   either `"script"` or `"module"`.
@@ -46,6 +52,8 @@ Significant diversions are expected to occur in the future such as streaming, EB
 
 - **plugins**: Array containing the plugins that you want to enable.
 
+- **strictMode**: TODO
+
 ### Output
 
 Babylon generates AST according to [Babel AST format][].