Add spec for disappearing whitespace (issue #67, #147)

spec/_files/disappearing_whitespace.js

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+var disappearing_whitespace = {
+  bedrooms: true,
+  total: 1
+};

spec/_files/disappearing_whitespace.mustache

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+{{#bedrooms}}{{total}}{{/bedrooms}} BED

spec/_files/disappearing_whitespace.txt

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+1 BED