Update parser.js

I should not multiply the translating values.
Fixes mathformla that was still outside the screen
Update parser.js

Restored parseUseDirectives functionality, maintaining getElementsByTagName and  changing logic of running trought the list.
Update parser.js

Don't miss A tags, they behave like g tags.
Merge pull request #1509 from asturur/viewbox-small-fix

Update parser.js