Msglite

* Fixed issue with embedded msg files caused by the changes in v0.23.0.

* [[mattgwwalker 75](https://github.com/Syncurity/msg-extractor/issues/75)] & [[Syncurity #39](https://github.com/Syncurity/msg-extractor/issues/39)] Completely rewrote the function `Message._getStringStream`. This was done for two reasons. The first was to make it actually work with msg files that have their strings encoded in a non-Unicode encoding. The second reason was to make it so that it better reflected msg specification which says that ALL strings in a file will be either Unicode or non-Unicode, but not both. Because of the second part, the `prefer` option has been removed.
* As part of fixing the two issues in the previous change, we have added two new properties:
1. a boolean `Message.areStringsUnicode` which tells if the strings are unicode encoded
2. A string `Message.stringEncoding` which tells what the encoding is. This is used by the `Message._getStringStream` to determine how to decode the data into a string.

* [[mattgwwalker 69](https://github.com/Syncurity/msg-extractor/issues/69)] Fixed date format not being up to standard.
* Fixed a minor spelling error in the code.

* [[Syncurity 30](https://github.com/Syncurity/msg-extractor/issues/30)] Added `--validate` option.
* [[Syncurity 24](https://github.com/Syncurity/msg-extractor/issues/24)] Moved all dev code into its own scripts. Use `--dev` to use from the command line.
* [[mattgwwalker 67](https://github.com/Syncurity/msg-extractor/issues/67)] Added compatability module to enforce unicode os functions.
* Added new function to `Message` class: `Message.sExists`. This function checks if a string stream exists. It's input should be formatted identically to that of `Message._getStringSteam`.
* Added new function to `Message` class: `Message.fix_path`. This function will add the proper prefix to the path (if the `prefix` parameter is true) and adjust the path to be a string rather than a list or tuple.
* Added new function to `utils.py`: `get_full_class_name`. This function returns a string containing the module name and the class name of any instance of any class. It is returned in the format of `{module}.{class}`.
* Added a sort of alias of `Message._getStream`, `Message._getStringStream`, `Message.Exists`, and `Message.sExists` to `Attachment` and `Recipient`. These functions run inside the associated attachment directory or recipient directory, respectively.
* Added a fix to an issue introduced in an earlier version caused by accidentally deleting a letter in the code.

* [[Syncurity 7](https://github.com/Syncurity/msg-extractor/issues/7)] Changed debug code to use logging module.
* [[Syncurity 26](https://github.com/Syncurity/msg-extractor/issues/26)] Fixed Attachment class using wrong properties file location in embedded msg files.
* [[Syncurity 4](https://github.com/Syncurity/msg-extractor/issues/4)] Improved handling of command line arguments using argparse module.
* [[Syncurity 24](https://github.com/Syncurity/msg-extractor/issues/24)] Started work on moving developer code into its own script.
* [[mattgwwalker 63](https://github.com/mattgwwalker/msg-extractor/issues/63)] Fixwed json saving not applying to embedded msg files.
* [[mattgwwalker 55](https://github.com/mattgwwalker/msg-extractor/issues/55)] Added fix for recipient sometimes missing email address.
* [[mattgwwalker 65](https://github.com/mattgwwalker/msg-extractor/issues/65)] Added fix for special characters in recipient names.
* Module now raises a custom exception (instead of just `IOError`) if the input is not a valid OLE file.
* Added `header_dict` property to the `Message` class.
* General minor bug fixes.
* Fixed a section in the `Recipient` class that I have no idea why I did it that way. If errors start randomly occurring with it, this fix is why.

* Fixed a tab issue and parameter type in `messages.py`.