fix some cross-references
Merge pull request #962 from tshepang/refs

fix some cross-references
Fix wrong reference to non existent getAjax function
Fix reST markup and spelling of "hand"
Remove extra word
Fix reST markup
my.package.MyJinja2Renderer is registered for .jinja2 files not .jinja
Fix typo that broke the reference to pyramid.events.NewRequest
Remove unused imports from code sample

The import should be done only when actually using the global registry.
Remove extra word
Use into instead of in to

Seems more correct and is consistent with the usage a few words further.
Fix grammar
Consistently link middleware term to the glossary
Add missing word
Remove extra word
Remove extra word
Improve phrasing