Make CFLAGS overridable.

If $CFLAGS is not last in the assignment, then you cannot override
flags like -O2.
Correction to: Record which promise set each variable.

Our current Promise may be a copy, that'll be free()d at the end of
the current convergence pass; comparing this to the Promise of a later
assignment won't be equal even if it's the original (or another copy
of it); and dereferencing it during reporting shall be regrettable.
Fortunately, a Promise's .org_pp records the original in any copies,
so we can record that instead, bypassing both problems.
Add data containers to meta promises, with acceptance test.
Make testall test what's in the current folder, not `dirname $0`.

This is so that it can be called directly from masterfiles.
Export variables to tests so we can find the enterprise plugin.
Redmine#1900: test basic template and trailing newline
Fix ExtractScalarPrefix, need to look ahead after dollar
Merge remote-tracking branch 'tzz/test/redmine4025-namespaced-bundles'
Revert "Redmine#3323: @include mechanism"

This reverts commit 3fc17367cb1ad78a007a41a8a554ac3f5566fb63.

Conflicts:
	libpromises/cf3lex.l
	libpromises/cf3parse.y
tests/acceptance: improve default_check_strcmp and add default_check_regcmp
Redmine#3122: acceptance test for list interpolation order
Ensure VarRefs with special scopes do not inherit a namespace.

Close #4025
Use CfReadLine (getline) in function regline, chop Chop.

This removes line length limitations and space truncation in Chop.

Close #3434, #1569
Redmine#3655: bundlesmatching() gets tag support
tests/acceptance: add generic classes and reporting
Redmine#3184: acceptance test for editing immutable files
Merge pull request #1303 from tzz/test/3184-editing-immutable-files

Redmine#3184: acceptance test for editing immutable files
Merge pull request #1291 from tzz/feature/meta-containers

Add data containers to meta promises, with acceptance test.
Redmine#3514: allow non-absolute paths for returnszero()
Merge pull request #1304 from tzz/bugfix/3514-returnszero-allow-non-absolute-paths

Redmine#3514: allow non-absolute paths for returnszero()