System.set and System.getForTesting.

System.set() takes a module.
System.getForTesting() is a backdoor, needed for test/unit once
    we merge static and dynamic modules.
Drive-by: fix Makefile for runtime-related rules.

Review URL: https://github.com/google/traceur-compiler/pull/658

Closes #658.
Report compile errors without throw, fixes #662

Review URL: https://github.com/google/traceur-compiler/pull/663

Closes #663.
Interpret modules

 Command line interpret mode adapted for import().

    Given a filename, convert it to a normalized module name.
    Clean up some leftover code.

Review URL: https://github.com/google/traceur-compiler/pull/656

Closes #656.
Resolve only names beginning with dot against referrerName

Review URL: https://github.com/google/traceur-compiler/pull/665

Closes #665.
Hard code RSVP version to 3.0.3

This is to redeuce diff noise due to different versions of RSVP on
different machines.
Trace normalizeName construction if the load fails

Review URL: https://github.com/google/traceur-compiler/pull/664

Closes #664.
Make pretty print an option of the ParseTreeWriter.

Make the tree writer take an option object containing a pretty print flag instead of hard coding to always use pretty printing.

Also, do not append a new line to the end o printing trees. We still append new lines after statements.

Review URL: https://github.com/google/traceur-compiler/pull/666

Closes #666.
Duplicate imports should be reported as errors

Fixes #648

Review URL: https://github.com/google/traceur-compiler/pull/667

Closes #667, closes #648.
Remove export symbol etc

Clean up our internal Symbols. The only one left after this is our ModuleSymbol.

Review URL: https://github.com/google/traceur-compiler/pull/668

Closes #668.
Extract --referrer prefix from package.json version.

node build/semverIncrement.js prints semver patch + 1 number and updates package.json
version and  devDependency version.
Require traceur node_module as devDependency.

Review URL: https://github.com/google/traceur-compiler/pull/669

Closes #669.
Remove loadSync from nodeLoader and webLoader

Left over cleanup from 39e76aca8fb1dc4b2e2f3361ad9b3c89e6ec5480

Review URL: https://github.com/google/traceur-compiler/pull/671

Closes #671.
Register traceur modules at 'traceur@'+<package.json version>.

Make target 'updateSemVer' will ncrement the PATCH semver field from package.json version.

Use System.getForTesting()

Review URL: https://github.com/google/traceur-compiler/pull/672

Closes #672.
Add missing devDependency, semver

TBR=johnjbarton

Review URL: https://github.com/google/traceur-compiler/pull/673

Closes #673.
Correct and test build/incrementSemver.js

The path must be computed properly for the write step, read '../package.json' works but not write.

Review URL: https://github.com/google/traceur-compiler/pull/674

Closes #674.
Fix issue with empty generators

When the function body does not contain any yield or return no state machine is created. If this happen we create a state machine with a single fall through state.

Fixes #301

Review URL: https://github.com/google/traceur-compiler/pull/676

Closes #676, closes #301.
Build using node_modules/traceur; don't commit bin/traceur.js

Review URL: https://github.com/google/traceur-compiler/pull/675

Closes #675.
Restore bin/traceur.js to commits.

Our loader support is not far enough along to allow us to switch to pure node_module builds.

TBR=@arv

Review URL: https://github.com/google/traceur-compiler/pull/678

Closes #678.