Check whether a month is followed by a year

Bug fix for #375
Handle POST_COST_VIRTUAL in print

Bug fix for #1046
Move the debug statement to where it makes more sense

It's possible to just say "select account" without a "from", so
put the debug statement at the end of the block where the variable
"formatter" is filled with the query string.
Fix query string for select account

A wrong query string was generated by "select account": one ansify_if()
too much was listed and justify() was called with the wrong parameters.

Bug fix for #744
Recognize --cleared-format option

Bug fix for #747
Remove character that wasn't displayed in ledger2
Improve backwards compatibility with ledger2

This brings some single character format strings in line with what
they actually meant in ledger2.

Bug fix for #755
Document --exchange COMMODITY1:COMMODITY2 syntax.

It appears this syntax does indeed work as described in this change, but the
feature was not previously documented herein.
Merge pull request #299 from bkuhn/document-exchange-option-with-colon

Document --exchange COMMODITY1:COMMODITY2 syntax.

Thanks!
acprep: remove dead code

This isn't used anywhere since 4681e58d7f3cda2a2ac6d05b6ec1a106f568e029.
Merge pull request #300 from jacknagel/patch-2

acprep: remove dead code
Don't lose commodity when cost is not separated by whitespace

When a cost was specified without a whitespace after the @ symbol,
as in @$5.01, this was incorrectly parsed as 5.01 (losing the
commodity) rather than $5.01.

Bug fix for #1050