Always attach a guardedHandlers property to TryStatements

Closes #48
Linting
Remove redundant if conditions that are tested above
parseMaybeUnary() doesn't need parameter @noIn
Line number start from 1 after getToken.jumpTo()
Pass on 'this' as root scope, for better inclusion of Acorn inside Paper.js

Use same approach as Esprima.
Fix bug with parsing slash after operator-keyword property

Closes #53
Further refine parseExprList indentation heuristic

Closes marijnh/tern#221
Fix special case to handle regexps that start with =

Closes #55
Improve error message for ++/re/

Closes #54
Fixed: have to return the value from the visitor.

Without this, preprocessor expressions always evaluate false because undefined is returned.
Fixed: no point in executing preprocessSkipToElseOrEndif() if not skipping.
Typo, formatting
Fixed: import of walk should be relative
Fixed: Repository url and some more attributes
Merge branch 'master' of https://github.com/marijnh/acorn

Conflicts:
	acorn.js