Changed the Highlight syntax and updated all toolkits to support the new syntax

This should be a rare change to the existing CriticMarkup syntax.
Previously we used `{{ }}` for highlights but there was a conflict with
several static blog templating engines that use a similar syntax.

The new syntax is `{== ==}` for highlights.
Adds BBEdit clippings for the CriticMarkup marks plus instructions on how to use them.
Create .gitignore, add .DS_Store to it.
Merge pull request #5 from DivineDominion/master

incorporate TextMate bundle
Merge pull request #6 from pdxmph/master

BBEdit Tools: Add clippings files plus instructions on use
Add BBEdit AppleScripts to search forward and backward for CriticMarkup marks in a document.
Merge pull request #7 from pdxmph/master

Utilities: BBEdit AppleScript to search forward and backward in a document for CriticMarkup marks
updating TextMate bundle submodule