updated install script to detect 'RC' versions
Merge pull request #963 from tjwebb/tags/R1_4_6

updated install script to detect 'RC' versions
issue #21684: unset item values when item is unset
issue #21684: isFractional
issue #21684: autonumbering of line items
issue #21684: isMisc on invoice line
issue #21684: apply isMisc read-onlys at start
issue #21684: invoiceTax model
issue #21684: invoiceAllocation model
issue #21684: first pass at aggregated fields
issue #21684: invoice relation and recurring invoice
issue #21684: update todo
Merge remote-tracking branch 'XTUPLE/master' into 21684
issue #21684: sales category must be added to invoice line by billing
issue #21684: best practices for require
issue #21684: take settings from customer
issue #21684: first pass at invoice triggers
issue #21684: invoice validation
issue #21831: Disable problematic trigger while clearing orms.
Merge pull request #974 from jrogelstad/tags/R1_4_6

issue #21831: Disable problematic trigger while clearing orms.