fix: better compiler error for empty templates

Fixes #243

Closes #244
docs: Precompiled, packaged & minified version

This commit updates the playground build to be precompiled (hsp, and js
transpiled) packaged and minified.

The goal is to optimize the initial display of the playground.

Closes #242
refactor: simplify and document regexp

Closes #247
feat(transpiler): adds options for global mode and variable name

This commit is a continuation of a223a0bc20d0070c48c9dd037d5b2b17c0fe0346
for the transpiler. It adds support for the following two options in the
transpiler:
* mode: either `"commonJS"` (default) or `"global"`, determines whether
the transpiler adds the call to require at the beginning of the transpiled
file or not
* setVarName: defaults to `"$set"`, determines the name of the variable
pointing to the `$set` module

When calling the compiler, the options object is passed directly to the
transpiler, so that the existing `mode` option of the compiler is reused
in the transpiler.

close #246

Closes #246
tests: verify that HTML tags containing - are considered valid
chore: retry certain steps on TravisCI to get more stable builds

http://blog.travis-ci.com/2013-05-20-network-timeouts-build-retries/

Closes #249
docs: using hashspace from CDN over HTTPS
docs: remove todomvc
chore: add size tracking for deliverables - part 1

Closes #258

Closes #258
build: don't execute packaging on npm install

Fixes #217

Closes #260
refactor: use Object.create polyfill

Closes #262
refactor: use pratt parser for if expressions