fix: use proper variable names

[b-admike]

Description

Fix to use proper variable names. Those using complex WSDLs will probably run into this issue with the following error:

/Users/badmike/loopback/strong-soap/example/json2xmlwithschema.js:57
      ].children[1].describe(wsdl.definitions),
        ^

TypeError: Cannot read property 'children' of undefined
    at /Users/badmike/loopback/strong-soap/example/json2xmlwithschema.js:57:9
    at /Users/badmike/loopback/strong-soap/src/parser/wsdl.js:105:9
    at WSDL._processNextInclude (/Users/badmike/loopback/strong-soap/src/parser/wsdl.js:162:14)
    at WSDL.processIncludes (/Users/badmike/loopback/strong-soap/src/parser/wsdl.js:221:10)
    at /Users/badmike/loopback/strong-soap/src/parser/wsdl.js:60:12
    at _combinedTickCallback (internal/process/next_tick.js:131:7)
    at process._tickCallback (internal/process/next_tick.js:180:9)

Related issues

• connect to <link_to_referenced_issue>

Checklist

• New tests added or existing tests modified to cover all changes
• Code conforms with the style
  guide