Heavily improved Tax Report & TXF export by Alex Aycinena.

Prints tax information sorted by Form/Schedule, tax code, account,
transaction and date instead of by account hierarchy. Allows any tax
code to be assigned to multiple accounts. No longer double counts
transactions when a parent account is not a placeholder and has
transactions posted to it. Converts non-USD accounts and transactions
to USD instead of adding across currencies. Provides an error dialog
instead of crashing gnucash when exporting a file without write
permission. Provides additional options to adjust the level of detail
shown on the report.

Patch by J. Alex Aycinena <alex.aycinena@gmail.com>.

git-svn-id: svn+ssh://svn.gnucash.org/repo/gnucash/trunk@17602 57a11ea4-9604-0410-9ed3-97b8803252fd

AUTHORS

@@ -103,6 +103,7 @@ Andrew Arensburger <arensb@cfar.umd.edu> for FreeBSD & other patches
 Matt Armstrong <matt_armstrong@bigfoot.com> for misc fixes
 Jon Arney <jarney1@cox.net> Windows porting patches, misc fixes
 A. Alper Atici <alper_atici@yahoo.com> Turkish translation
+J. Alex Aycinena <alex.aycinena@gmail.com> Heavily improved Tax Report & TXF export
 Fred Baube <fred@moremagic.com> for attempted Java port/MoneyDance
 Roman Bertle <bertle@smoerz.org> Austrian German account templates
 Jan-Pascal van Best <j.p.vanbest@tbm.tudelft.nl> MT940 importer