Check validity of constraints' lvalues during PolicyCheckPartial().

The same check existed in the parser so I removed it. Validity of constraints
is now checked in ConstraintCheckSyntax(), copied from ConstraintGetSyntax()
which now expects syntax is already checked.

Also fixed a segfault, so changed the relevant acceptance test to not expect
crash, but just failure.
Fix incorrect context bug and move to paths array
The context "all" is not automatically defined like "any", this caused
the automatic contexts for path definition and path existance to never
be defined. Switching to array for path definitions allows the use of
getindices to build the list of all paths automatically instead of
manually. Top level path variable definition for backward compatibility
still exists.
add namespaced acceptance tests as per https://cfengine.com/dev/issues/1400
Fix segfault with duplicate handles. Issue #2267
Merge pull request #404 from tzz/tests/array-across-namespaces

add namespaced acceptance tests (try#2)
Merge pull request #405 from baptr/issue-2267

Fix segfault with duplicate handles. Issue #2267
Merge pull request #397 from jimis/bug2230

Check validity of constraints' lvalues during PolicyCheckPartial().
Expose qualified name utility functions in policy.h
Avoid detached ad-hoc promise in runagent
Privatize IsBody, IsBundle
Fix for acceptance tests.

It turns out that using printf and stat is not such a good idea, since
their behavior change from platform to platform.
This commit changes the mode test to a little perl script.
Attach ad-hoc promise in FnCallSelectServers
Attach ad-hoc promise in cf-execd StartServer
Attach ad-hoc promise in monitord MonitorStartServer
Fix segfault in monitord, caused by incorrect decl
Attach ad-hoc promise in serverd StartServer
Remove NewPromise
Move, rename promises:HashPromise -> policy:PromiseHash, constify
Remove unused function params
Constify, remove unused parameters in evaluation