v0.7.4

• Organise and comment properly ALL widget presenters (children of SpAbstractWidgetPresenter) that are needed to create SpPresenter compositions.
• Add missing examples for all widget presenters.
• Presenter comments are now implemented through a microdown template, showing interesting sections and pointing to correct API to use (along with examples).
• SpAbstractWidgetPresenter hierarchy now understands selectFirst.
• New presenter SpTreePresenter. A tree with just one column.
• SpTreeTablePresenter now understands expandPath: and expandRoots.
• Added SpLinkTableColumn to add links to tables (and trees).
• New utility presenter: SpListWithFilterPresenter.
• Fixed alignment of cells on SpGridLayout.
• SpGridLayout axis constraints now understand alignment (because sometimes you want to align a whole column, not just a cell).
• Several fixes on commands for Pharo interaction.
• Lots of small bugfixes.