rose_arch: friendlier error messages
metomi/rose#597: improve colour parse failing
rose app-run: test incr SVN sources file install
rose app-run: report correctly ref to ! namelist

Instead of failing with a None exception.
Merge pull request #908 from matthewrmshin/rose-app-run.ignored-namelist

rose app-run: report correctly ref to ! namelist
t/rosa-db-create: fix fixed user ID
Merge pull request #909 from matthewrmshin/fix.t.rosa-db-create

t/rosa-db-create: fix fixed user ID
Merge branch 'master' into t.rose-app-run.file-incr-2
rose_arch: add tests for bad configuration errors
rose_arch: add unbound error test
Merge pull request #904 from matthewrmshin/t.rose-app-run.file-incr-2

rose app-run: test incremental SVN sources file install
metomi/rose#597: changes following review
Merge pull request #896 from benfitzpatrick/rose-arch.fix-unbound

rose_arch: friendlier error messages
rose.popen: ensure OSError has a filename

OSError is normally raised if a command cannot be executed.
t/rose.popen: connected
Merge pull request #901 from benfitzpatrick/597.colour-spec

#597: improve colour parse failing
Merge pull request #912 from matthewrmshin/rose.popen.oserror

rose.popen: ensure OSError has a filename