Fix parsing error with lodash

[travoltron]

When using this library with Babel and lodash, an error arises when trying to send an SMS, or make any changes that require the _.template function to get called.
SyntaxError: Unexpected token = at Function (<anonymous>), specifically source: 'function(obj) {\nobj || (obj = {});\nvar __t, __p = \'\', __j = Array.prototype.join;\nfunction print() { __p += __j.call(arguments, \'\') }\nwith (obj) {\n__p += \'/Accounts/\';\n= sid ;\n__p += \'.json\';\n\n}\nreturn __p\n}'

To alleviate this, I broke up the template parsing to use concatenated strings, rather than interpolation.

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[childish-sambino]

@travoltron Could you provide sample code that illustrates the issue you're running into?