fixed CommonJS check

QUnit defines module too. If you try to use mustache in a QUnit and AMD environment it won't work
Merge pull request #243 from kannix/patch-1

more stringent CommonJS check
throw inside the if
Use exported escaping function

Fixes #244
Use JavaScript's definition of falsy

Fixes #186
Remove newlines
Track changes in CHANGES
Add volo support

Fixes #249
Version 0.6.0
Text passed to higher-order sections unrendered

Fixes #187
More concise token format
Coerce { token types to &
Make high-level API same as Renderer API

Also, allow partials to be passed to the function that is returned
for pre-compiled templates. This makes the API more consistent all
around, but comes with the caveat that renderers are much more
aggressive at caching. Now, any time a template or partial is
compiled with the same name as a previously compiled template the
cached version is used.

Fixes #240
Add tests for null view
Replace code generation with straight function execution.

This is a strict port of the existing process - there are many opportunities for optimization based on this.
Don't use eval

Fixes #207 #210
Rename Renderer => Writer
Better variable names
Prevent global var leak

Also, changed order of arguments to internal render function.
Use exported parse function