With this patch, we make sure the height we query is the one matching
the width we stored and not a newer or older one.

This only fixes the sizing problem, the rendering issue visible in
some situations is still present.

This fix is replicated from the fix in libview's WrapLabel, see
http://view.svn.sourceforge.net/viewvc/view/trunk/libview/libview/wrapLabel.cc?revision=132&view=markup
It also includes the "fix for the fix",
http://view.svn.sourceforge.net/viewvc/view/trunk/libview/libview/wrapLabel.cc?revision=135&view=markup

Since the license is a huge piece of text expected to possibly scroll
horizontally, and since most themes display the background of text
views in a different color than the default widget background color,
adding a shadow makes the edges more visible and the UI neater.

If the 'default' style isn't set to a named style, then probably the
filetype styles have been overridden with manual colors and may not
work properly with color schemes.

Note: HTML-based filetypes won't show a warning because they don't
have a 'default' style (they use 'html_default' instead).

This is a simple heuristic, but is worth having to avoid some
spurious bug reports when using the color schemes dialog.

Scintilla mentions clearing styles after setting lexer.

This fixes styles being cleared when using the Split Window plugin.

Current color scheme was applied upon color scheme selection dialog
display because the GtkTreeView::cursor-changed signal is emitted when
the tree view is initially shown (since it actually gets the focus for
the first time), uselessly re-applying the current color scheme.

This is a performance issue because when many documents are open
updating the color scheme can take a few seconds.

Now we watch for the GtkTreeSelection::changed signal on the tree
view's selection, which is only emitted when the selected item actually
changes.  We also connect to that signal after filling the tree so we
don't get notified on the initial selection setup.

Now there is a dialog instead of a menu for selecting the color
schemes, the item under View->Editor can be created with Glade like the
rest of the menu.

This prevents GCC from complaining about implicit casts and comparisons
between different pointer types.  It also makes the code a little less
bound at dealing with TMTags.

This allows the user to define a label to be displayed in the menu in
place of the command to be run.  This can be very useful if e.g. a
custom command is too complex to be easily read in the menu, or if two
custom commands are so similar could be confounded.

This ensures we call the genapi.py script with the same Python interpreter as the Waf
build system was called. This is relevant if the used interpreter is not 'python' but e.g.
python2 or python2.6 or whatever.

This prevents the parser getting confused.

Use a generic match code and an array of the mappings for easier code
maintenance.

This removes 'Replacing the default C/C++ tags file' - we should
not encourage users to do this as it's unnecessary and error-prone
when updating Geany.