Enable querying compile-time --[no-]checks setting at execution time.

[Reviewed by Sung.]

Add the const variable CHPL_NO_CHECKS to the compile-time configuration
flags in chpl_compilation_config.h.  This will enable a launcher or user
executable to know at execution time whether --no-checks was thrown at
compile time (including implicitly, due to --fast being thrown).


git-svn-id: http://svn.code.sf.net/p/chapel/code/trunk@23787 3a8e244f-b0f2-452b-bcba-4c88e055c3ca
Change tests with extern prototypes to C library functions to use c_string rather than string



git-svn-id: http://svn.code.sf.net/p/chapel/code/trunk@23788 3a8e244f-b0f2-452b-bcba-4c88e055c3ca
Fix externProcInClassShouldBeError.chpl and change its future messages

This test should have been changed with the proc = signature changes
(no .bad file made it pretty much impossible to spot).

After updating, the test no longer fails in the way it originally did
(internal error).  Not sure what fixed the problem along the way, but
it now fails in a somewhat less confusing way (during C compile), so
I've turned this into an error message future (or maybe it should be a
"warning message" future).



git-svn-id: http://svn.code.sf.net/p/chapel/code/trunk@23789 3a8e244f-b0f2-452b-bcba-4c88e055c3ca