set BZR_HOME env var so bzr won't fail

Dependencies

• [2] VOBFCHIX use top_srcdir in stead of srcdir
• [3] WFJ3ZPRM add tests for scm inputs
• [4] G2ZB6464 first test, not yet in buildprocess
• [5] I3TU2UJQ
• [6] OSZDLGMP add target to make simple git/hg/svn inputs
• [7] DCHQR576 add bzr-repo target
• [8] 7RO7CINM setup environment variables for tests
• [9] WHS5RMPO

Change contents

• edit in tests/Makefile.am at line 31
  [2.112]

  [4.252]
  +

  + repos : dirs git-repo hg-repo svn-repo svn-checkout-repo bzr-repo bzr-checkout-repo
• replacement in tests/Makefile.am at line 34
  [4.253]→[3.158:236](∅→∅)
  − dirs : git-repo hg-repo svn-repo svn-checkout-repo bzr-repo bzr-checkout-repo
  [4.253]

  [4.157]
  + dirs :
• replacement in tests/Makefile.am at line 60
  [4.150]→[4.150:205](∅→∅)
  − bzr whoami "build <build@donotemail.com>" -d bzr-repo
  [4.150]

  [4.205]
  + BZR_HOME=$(abs_builddir)/data bzr whoami "build <build@donotemail.com>" -d bzr-repo
• replacement in tests/Makefile.am at line 63
  [4.257]→[4.257:305](∅→∅)
  − bzr commit -m "add bzr-file" bzr-repo/bzr-file
  [4.257]

  [4.305]
  + BZR_HOME=$(abs_builddir)/data bzr commit -m "add bzr-file" bzr-repo/bzr-file
• edit in tests/Makefile.am at line 70
  [3.346]
  +