Fix wrong model recognition

Parser was recognizing words with `model` keyword combination, for example `` `model` `` or `Cmodel`, as model, this is a suggestion to fix the issue. this pull request would close issue #92 and #152.
@zdne true, but in two other regex, `RequestRegex` and `ResponseRegex`, having zero or more spaces before the keyword has been added so I thought there might be reason for it and it should be followed in `ModelRegex`.(I did not changed the the logic but added more condition to limit exceptions)