Runtime string support clean up and refactoring.

This commit moves the launcher-shared C string functions into
chpl-string-support.[ch] and changes the Makefile and other files
appropriately.  I took the opportunity to pare down the #included
files in chpl-string.c and chpl-string-support.c to only what is
needed.

In addition, some remaining invalid uses of chpl_string are removed.
Merge branch 'master' of github.com:chapel-lang/chapel into test
Further re-shuffling.
Look instead for the first '<', as some test scripts add arguments after execopts
Merge pull request #119 from benharsh/stdin-in-execopts

Fix stdin execopts to look for first instance of '<'

Some of our automated tests add arguments after those in execopts, and we were only looking at the last two arguments. This fix will look for the first instance of '<', instead of looking at the second-to-last argument.
Add comments at the top of chpl-string-support.[ch] about the file and
possibly renaming of the file as well as the functions within.
Merge branch 'master' of github.com:chapel-lang/chapel into test
Merge pull request #118 from sungeunchoi/test

Runtime string support clean up and refactoring

[reviewed by David]

This commit moves the launcher-shared C string functions into chpl-string-support.[ch] and changes the Makefile and other files appropriately. I took the opportunity to pare down the #included files in chpl-string.c and chpl-string-support.c to only what is needed. In addition, some remaining invalid uses of chpl_string are removed.

We should consider renaming chpl-string-support.[ch] and the functions within at some point when the string stuff has settled down.
The first try, with work-in-progress artifacts
Removing the work-in-progress artifacts (comments, printouts)
Also reorder in CallInfo data
Remove debugging support
Polish: removed references to "wrapper"; made the function return void"
Added a comment based on Tom's review
Merge pull request #121 from vasslitvinov/rr

Compiler/resolution: do not create order wrappers.
Instead, when needed, reorder the call actuals directly.

Order wrappers are mentioned in svn:r1358 - see ACallbacks::order_wrapper(),
and were introduced before that. We no longer know why we were not
reordering the actuals directly back then.

As to the order of any side effects that may happen while evaluating
the actuals: I believe that any side effects are flattened during
normalization into statements that preceed the CallExpr. The actuals,
I expect, are all just symbols, so it does not matter (mostly) what order
to pass them in.

I will add separately a test that highlights the evaluation order.
Its output differs from what would be produced by the rule "evaluate
the actuals in the order they appear in the call". However, the spec
does not seem to define the order of evaluating the actuals, and the
output of the test is unaffected by this change.

IMPLEMENTATION NOTES

This turned out to be a simple change.

I renamed the function and made it return void, to make it clear
that it will never create a wrapper. I left its definition and
its call in the spots where they have been, partly to preserve
history, partly because I did not see any better spots for them.

reviewed by: David, Tom