gnucash maint: Multiple changes pushed

[John Ralls]

Updated	 via  https://github.com/Gnucash/gnucash/commit/28691b46 (commit)
	 via  https://github.com/Gnucash/gnucash/commit/b1ee7c6e (commit)
	 via  https://github.com/Gnucash/gnucash/commit/704afc6e (commit)
	 via  https://github.com/Gnucash/gnucash/commit/fe73f52b (commit)
	 via  https://github.com/Gnucash/gnucash/commit/4e88b8cb (commit)
	from  https://github.com/Gnucash/gnucash/commit/93f3a8ea (commit)



commit 28691b46ba5fc198eaddf133d48c5696421915b9
Author: John Ralls <jralls at ceridwen.us>
Date:   Sat Aug 18 12:36:22 2018 -0700

    Create srfi-64 tests for gnucash/report/report-system/commodity-utils.scm.

commit b1ee7c6eec8b18647213d955bdd4b229815a438a
Author: John Ralls <jralls at ceridwen.us>
Date:   Fri Aug 24 14:25:43 2018 -0700

    Clarify and de-duplicate sumlist and report-list descriptions.
    
    Also correct descriptions of gnc:get-exchange-totals and
    gnc:get-exchange-cost-totals. Neither calculates prices.

commit 704afc6e02fc78f7d8669f6b4ef3be239c05e543
Author: John Ralls <jralls at ceridwen.us>
Date:   Fri Aug 24 14:25:04 2018 -0700

    Comment to explain structuring an (env-transfer-foreign).

commit fe73f52bdbdecfe73797aacc327d50f67f29d68d
Author: John Ralls <jralls at ceridwen.us>
Date:   Mon Aug 27 18:00:55 2018 -0700

    Guard against divide-by-zero errors.

commit 4e88b8cb6c2c2715522a9fe0d5e636c0286530a5
Author: John Ralls <jralls at ceridwen.us>
Date:   Sat Aug 18 16:19:43 2018 -0700

    Remove the number-collector.
    
    It is redundant and incorrect since gnc-numeric was replaced with Scheme
    rationals in the report code.



Summary of changes:
 gnucash/report/business-reports/receipt.scm        |   2 +-
 gnucash/report/business-reports/taxinvoice.scm     |   2 +-
 .../report/report-system/commodity-utilities.scm   | 133 ++---
 gnucash/report/report-system/report-utilities.scm  |  43 +-
 gnucash/report/report-system/test/CMakeLists.txt   |   1 +
 .../report-system/test/test-commodity-utils.scm    | 590 +++++++++++++++++++++
 libgnucash/engine/test/test-extras.scm             |  16 +-
 7 files changed, 685 insertions(+), 102 deletions(-)
 create mode 100644 gnucash/report/report-system/test/test-commodity-utils.scm