The regex account aliases added in 0.24 trip up people switching between
hledger and Ledger. (Also they are currently slow).
This change makes the old non-regex aliases the default; they are
unsurprising, useful, and pretty close in functionality to Ledger's.
The new regex aliases are also available; they must be enclosed in
forward slashes. Ledger effectively ignores these, which is ok.
Also clarify docs, refactor, and use the same parser for alias
directives and alias options
077e3c6a02