Allow parallel edits

* Wait to open the journal until after getting text
* Use mktemp so that editors like vim get separate files for editing
Allow 'text' and 'markdown' aliases in export to dir

Fixes #201
Fixes error when exporting txt files

Fixes #202
Merge pull request #204 from chrissexton/parallel_edits

Allow parallel edits
Version bump
Export to xml
Better unicode mock support
Fixes unicode errors in XML export
Cleans up entry
Docs
Merge branch 'pr/211' into 2.0-rc1