ntdll/tests: Add tests for (Rtl)IsTextUnicode to verify that IS_TEXT_UNICODE_CONTROLS and IS_TEXT_UNICODE_REVERSE_CONTROLS are not mutually exclusive.

Tests for undo coalescing from previous patches sent as suggested by
Alex Villacís Lasso.

The bCaretAtEnd value in ME_TextEditor is used to identify that the
caret is at the end of a wrapped line instead of the start of the next
line in the paragraph since both these positions correspond to the
same position in the document. The bCaretAtEnd value was previously
being set back to FALSE whenever the window was resized.

Player names can be 31 characters long in Windows, so winemine should
now be able to read any of the player names in the registry created from
the minesweeper in the native Windows.

There were a few lines of code that I removed that explicitly kept the
number of mines and the timer unlit before the game started.  This isn't
consistent with Windows, so I don't know what the purpose was for doing
this.  In fact, it prevents the number of mines from being shown ahead
of time, which is useful information.