Add -E support in executables, for use by launchers in forwarding the
environment to the user program processes when the underlying system
launcher can't do so.  The changes are:

runtime/src/arg.c
  Add -E option parsing and environment variable setting.

doc/release/README.executing
  Document the new option.

test/execflags/ferguson/help2.good
test/execflags/shannon/configs/help/basehelp.txt
test/execflags/shannon/help.good
  Update the expected "-h" output.

test/execflags/gbt/dash-E-1-opt.chpl
test/execflags/gbt/dash-E-1-opt.execopts
test/execflags/gbt/dash-E-1-opt.good
test/execflags/gbt/dash-E-1-opt.skipif
test/execflags/gbt/dash-E-2-opts.chpl
test/execflags/gbt/dash-E-2-opts.execopts
test/execflags/gbt/dash-E-2-opts.good
test/execflags/gbt/dash-E-2-opts.skipif
  New unit tests.
Merge branch 'master' of github.com:chapel-lang/chapel into dash-E
Initial support for specifying stdin file in execopts
Using execopts stdin file for knucleotide
Using execopts stdin file for reverse-complement
Ready for unit testing.
Merge branch 'master' of github.com:chapel-lang/chapel into dash-E
Snapshot:
- update parseArgs() to know whether it's the launcher or user
  executable and whether it's parsing -E options or others
- call parseArgs() early to do -E options in main, later for the rest
- call parseArgs() in the launcher
- Merge the two dash-E tests into one, with two .execopts entries.
Merge branch 'master' into stdin-in-execopts
Produce an error if a .stdin file exists and one is specified in execopts
Add chpl_free_c_string() and use it to clean up leaked c_strings in
string and IO code.
Merge branch 'master' of github.com:chapel-lang/chapel into c_string-leaks
Resolves all but 3 of compile-time failures.
Removed assertion that the PRIM_INIT clause in preFold is never reached.
Fix a few bugs with PRIM_TYPE_INIT.

resolveCall() must apply default generic type resolution to the PRIM_TYPE_INIT primitive.

CallExpr::prettyPrint() had to be updated to recognize PRIM_TYPE_INIT as an "unusual"
case.
Merge branch 'master' into addPrimTypeInit

Conflicts:
	compiler/passes/scopeResolve.cpp
Getting rid of qio_channel_filelength and instead adding qio_channel_get_channel_size
Added a bug future whereby the compiler crashes when a task intent's ref clause includes a reference to a field.

From the .future: instead an error should be generated.
That's because fields are not subject to forall intents.
Even fields of a record.

Also, my anticipated implementation of forall intents will likely hit
the same issue.

P.S. This should really be 8 distinct tests, to ensure that an error
is generated for each case. The param 'if' I am using does not guarantee
that - because the compiler may generate the error prior to resolution.
So ideally split this into 6 tests once the bug is fixed,
the add two for forall intents when those are working.
Merge pull request #85 from vasslitvinov/task-intents--field-in-ref-clause--bug

Added a bug future whereby the compiler crashes when a task intent's ref clause references a field.

From the .future: instead an error should be generated.
That's because fields are not subject to forall intents.
Even fields of a record.

Also, my anticipated implementation of forall intents will likely hit
the same issue.

P.S. This should really be 8 distinct tests, to ensure that an error
is generated for each case. The param 'if' I am using does not guarantee
that - because the compiler may generate the error prior to resolution.
So ideally split this into 6 tests once the bug is fixed,
the add two for forall intents when those are working.
Switching to use qio_channel_get_offset_unlocked and qio_channel_get_end_offset_unlocked