Release2 dot0 save game fixes

I've coded a fix that seems to work for #13.  There will be additional save file fixes, so it's up to you if this should be merged now or if we should wait for the others.  Thus you should not close #13 yet.

I found that the patch by devEd was incomplete - in addition to incorrect variable names, it needed logic to save/load the xml and call the Set_Type method in the cLevel_Player class.

NOTE: The save xml file format changes with this change by adding a new field.  You will have to delete your old save files before using the game with this change.  Otherwise you will get a core dump when it tries to preview the files or load them.

This is what the new part of the xml looks like for the save file:
~~~~~~~~~~~~~~~
<player>
    <property name="lives" value="3"/>
    <property name="points" value="1500"/>
    <property name="goldpieces" value="0"/>
    <property name="type" value="2"/>
    <property name="type_temp_power" value="0"/>
    <property name="state" value="0"/>
    <property name="itembox_item" value="0"/>
    <property name="level_time" value="11594"/>
    <property name="overworld_active" value=""/>
    <property name="overworld_current_waypoint" value="0"/>
  </player>
~~~~~~~~~~~~~~~

Other notes:
* I have found that the time remaining for ghost maryo does not appear to be saved
* The invincibility state does not save.
* I added my QT Creator git ignore entry.  There is a risk I will accidentally commit my user settings if I don't get this committed to the release branch.
@Quintus, the reason I normally use // for each line in a set of lines is because C++ does not allow nesting of /* */.  For example:
~~~~~~~~~~~~~~~~~~c++
/*
/*
*/
*/
~~~~~~~~~~~~~~~~~~
--will not compile.

I like to use /* */ to comment out large sections of code to deactivate them, and this runs into issues when the said code already has /* */ for multiline comments describing the code.

Yes, sometimes editors can sometimes comment out code for you when you need to deactivate it, but this also falls apart when they simply dump /* */.  Only if an editor uses // do you avoid these issues.  I have seen Visual Studio insert /* */ in some cases, and I assume many other editors will do the same.