Refactor code to pull posting format into separate defun. Added reconcile buffer header and line configuration defcustom.
ledger-reconcile-compile-format-string returns a lambda that is used to format the posting data
Updated out of date value expression section in the documentation.
Fix to 90519fc6e132bd (moved paragraph to end of section).
Merge pull request #307 from redstreet/master

Updated out of date value expression section in the documentation.
Finished configurable reconcile format line.
Merge branch 'ledger-mode-bbug-875-configurable-reconcile-line'