MainWindow: Use a map instead of an array for Tools menu

[irrenhaus3]

Old behavior: When clicking the n-th item in the Tools menu, MainWindow looks up the n-th entry in the m_tools array and instantiates the PluginView stored there.

New behavior: When clicking an item in the Tools menu, MainWindow retrieves the object name of the QAction belonging to that item, and looks up that object name in the m_tools map and instantiates the PluginView stored under that name.
The object name is constructed from the plugin's display name when populating the Tools menu.

This makes the menu more maintainable and allows for things like submenus and non-plugin tools.

Additional changes:

• Rename showTool() to showPluginTool() and change the parameter from QAction* to QString const&.
• Format header file w.r.t. pointer/reference notation attaching to the type instead of the variable name.

[sakertooth]

Just a few formatting changes and readability enhancements.

[superpaik]

Just a few formatting changes and readability enhancements.

How about deleting the underscore in function parameters? At least in the .h file, where the variable is only used once.

Tested OK in windows 10/64b.

[sakertooth]

Just a few formatting changes and readability enhancements.

How about deleting the underscore in function parameters? At least in the .h file, where the variable is only used once.

Tested OK in windows 10/64b.

Just checked against the coding conventions, and yes, that should be done where applicable as well.

[irrenhaus3]

I'd prefer doing that kind of stuff in a separate PR, not only removing leading underscores but also changing parameter names to something more expressive than the 1-2 letter names we currently have.

[sakertooth]

I'd prefer doing that kind of stuff in a separate PR, not only removing leading underscores but also changing parameter names to something more expressive than the 1-2 letter names we currently have.

It wouldn't hurt to change it here, but I wouldn't consider it blocking by any means.

[PhysSong]

I wonder why you use displayName while there is also name. Plugins are instantiated using name, so I guess name is more natural here.

[JohannesLorenz]

@irrenhaus3 Friendly reminder that this has an open comment.