message: Update mapper function descriptions.
  Added string.equalsignorecase()
  Added string.substring()
  Added array.length()
diff: -
  +/* tslint:disable:max-line-length */
  export function getFunctions() {
  return {
  + array: {
  + type: 'namespace',
  + functions: {
  + length: {
  + name: 'length',
  + args: [
  + {
  + name: 'arr',
  + type: 'array'
  + },
  + ],
  + help: {
  + description: 'Returns the length of the array',
  + example: 'array.length(someArray)\n Returns 3',
  + usage: 'array.length(<<array>>)',
  + },
  + }
  + },
  + },
  'string': {
  'type': 'namespace',
  'functions': {
  @@ -28,7 +47,7 @@ export function getFunctions() {
  'name': 'equals',
  'args': [
  {
  - 'name': 'str',
  + 'name': 'str1',
  'type': 'string'
  },
  {
  @@ -38,11 +57,30 @@ export function getFunctions() {
  ],
  'return': {'type': 'boolean'},
  'help': {
  - 'description': 'Returns whether those two string are equals.',
  - 'usage': 'string.equals(<< str >>, <<str2>>)\nReturn Type\nboolean',
  + 'description': 'Returns whether strings str1 and str2 are equal.',
  + 'usage': 'string.equals(<<str1>>, <<str2>>)',
  'example': 'string.equals(\'Flogo Web\', \'Flogo Web\')\nReturns\ntrue'
  }
  },
  + 'equalsignorecase': {
  + 'name': 'equalsignorecase',
  + 'args': [
  + {
  + 'name': 'str',
  + 'type': 'string'
  + },
  + {
  + 'name': 'str2',
  + 'type': 'string'
  + }
  + ],
  + 'return': {'type': 'boolean'},
  + 'help': {
  + 'description': 'Compares this one string to another string, ignoring case considerations. Returns true if equal.',
  + 'usage': 'string.equalsignorecase(<<str1>>, <<str2>>)',
  + 'example': 'string.equalsignorecase(\'FLOGO WEB\', \'Flogo Web\')\nReturns\ntrue'
  + }
  + },
  'length': {
  'name': 'length',
  'args': [{
  @@ -55,7 +93,30 @@ export function getFunctions() {
  'usage': 'string.length(<< str >>)\nReturn Type\nint',
  'example': 'string.length(\'Flogo Web\')\nReturns\n9'
  }
  + },
  + 'substring': {
  + 'name': 'substring',
  + 'args': [
  + {
  + 'name': 'string',
  + 'type': 'string'
  + },
  + {
  + 'name': 'position',
  + 'type': 'integer',
  + },
  + {
  + 'name': 'length',
  + 'type': 'integer',
  + }
  + ],
  + 'return': {'type': 'string'},
  + 'help': {
  + 'description': 'Returns a substring starting at the position specified by the second argument. Character positions are numbered from 0.',
  + 'usage': 'string.substring(<<string>>, <<position>>, <<length>>)',
  + 'example': 'string.substring("Flogo is the most awesome project ever", 18, 7) \nReturns "awesome"'
  }
  + },
  }
  },
  