gnucash-docs: New annotated tag '3.903'

[John Ralls]

        at  https://github.com/Gnucash/gnucash-docs/tree/d562c13f215fb18278cb570e903cb6e5ba9f5c12 (tag)
   tagging  b341bb7e7898396674d14005fb7d5457758e4a24 (commit)
  replaces  3.901
 tagged by  John Ralls
        on  Sun May 31 14:53:10 2020 -0700


Tag Documentation Release 3.903.

David Cousens (2):
      Modifications to Guide Ch12 to include multi-currency transactions using trading accounts.
      Minor Correction to Help Manual

Frank H. Ellenberger (6):
      Minor imrovements on Invoice ID
      Minor fixes from the PR #138 discussion
      Improve links to Selingers tutorials
      Merge PR #137 into maint
      Merge branch 'maint'
      L10N of "Improve links to Selingers tutorials"

John Ralls (3):
      CI for gnucash-docs should be on Ubuntu 18.04 to match gnucash.
      Merge branch 'maint'
      Release GnuCash Documentation 3.903.