Upgrade version for v2.4.1 final release

Upgrade version for v2.4.1-beta3 release

Update version and CHANGELOG for v2.4.1-beta2 release

Fix crash during export of transations after upgrade to v2.4.1-beta1
   The commodities table was replaced, however, there are references to
   the commodities in the transactions

Remove GnuCash Android Google+ Community Page link (Google+ is dead)

Update CHANGELOG for v2.4.1 release

Update version for first beta release

Update version numbers and CHANGELOG in prep for v2.4.0 release