Add various documentation

[CrashTestJava]

• Add images to MouseCursor page; closes Add images to MouseCursor types #138
• Document mouseCursor changes; closes Document mouseCursor changing to mousecursor #137
• Document Dialog:file() title parameter; closes Document Dialog:file() title parameter #135
• Document autofit and sizeHint properties; closes Document autofit and sizeHint properties for Dialog #130
• Document about why app.clipboard.image transformations don't work; closes Document about why app.clipboard.image transformations don't work #125
• Expand/finish app.useTool() docs; closes Expand app.useTool() docs #141
• Reorder app.md
• Clarify pref.xml on app.preferences page

[CrashTestJava]

A few notes for the file parameter changes:

• For the filename parameter, I excluded the table portion, in my testing it didn't seem to do anything (might be a bug or I just used it incorrectly?)

• There were 2 versions of the open and save parameter documentation, I consolidated them down to one. One of the save parameters was named "load", which I assume is just a typo (as I couldn't find any mention of it in the code)