Revise keys in number-compare-strings_en.json

[pixelzoom]

From the CRC:

Make sure the string keys are all perfect, because they are difficult to change after 1.0.0 is published. Guidelines for string keys are:

(1) Strings keys should generally match their values. E.g.:

"helloWorld": {
  value: "Hello World!"
},
"quadraticTerms": {
  value: "Quadratic Terms"
}

Inspecting number-compare-strings_en.json, these 2 strings keys should be changed to match their values. The keys should be "isGreaterThan" and "hearNumberSentence" respectively. @chrisklus do you agree?

  "isMoreThan": {
    "value": "{{greaterNumber}} is greater than {{smallerNumber}}"
  },

 "readAloud": {
    "value": "Hear Number Sentence"
  }

[pixelzoom]

I took care of this in the above commit. @chrisklus please review. Close if OK.

[chrisklus]

Thanks @pixelzoom, commits look great. "isMoreThan" also needed to be renamed in babel since that string was already published. But I double checked the commit history (in number-play-strings_en.json since it was originally published as part of Number Play), and the string value was changed to "{{greaterNumber}} is greater than {{smallerNumber}}" before publication, so the translated values are correct, just the keys needed to be updated.

I think we are all set to close here.