Make narrowWideReferences its own pass.
Dereference widenMap at the call site.
Update compilerPerformance.perfkeys with new pass.
Merge remote-tracking branch 'upstream/master'
io: add function isDir

This function will check whether the given path is a directory.
io: add isFile

This function will check whether the given path is a regular file.
Merge branch 'master' of https://github.com/chapel-lang/chapel
add error checking on number of captures
add error checking on overflow in allocation for MAYBE_STACK_ALLOC
support octal in writef/readf
 fix unused variable
 add octal tests
include octal as base specifier
Octal print test now passes
Adding spec entry for HeapSort
Fixing a typo; Adding a note about the reverse argument
Adding note for specifying stdin file in execopts
Initial draft of sets README
Initial draft of lsq readme
Move README.knc to platforms directory.