feat: move "basic" grid pagination logic to wuttaweb

so far only "simple" pagination is supported by wuttaweb, so basically
the main feature flag, page size, current page.  in this
scenario *all* data is written to client-side JSON and Buefy handles
the actual pagination.

backend pagination coming soon for wuttaweb but for now tailbone still
handles all that.

tests/grids/test_core.py

@@ -19,6 +19,32 @@ class TestGrid(WebTestCase):
         grid = self.make_grid('foo')
         self.assertIsInstance(grid, mod.Grid)
 
+    def test_deprecated_params(self):
+
+        # component
+        grid = self.make_grid()
+        self.assertEqual(grid.vue_tagname, 'tailbone-grid')
+        grid = self.make_grid(component='blarg')
+        self.assertEqual(grid.vue_tagname, 'blarg')
+
+        # pageable
+        grid = self.make_grid()
+        self.assertFalse(grid.paginated)
+        grid = self.make_grid(pageable=True)
+        self.assertTrue(grid.paginated)
+
+        # default_pagesize
+        grid = self.make_grid()
+        self.assertEqual(grid.pagesize, 20)
+        grid = self.make_grid(default_pagesize=15)
+        self.assertEqual(grid.pagesize, 15)
+
+        # default_page
+        grid = self.make_grid()
+        self.assertEqual(grid.page, 1)
+        grid = self.make_grid(default_page=42)
+        self.assertEqual(grid.page, 42)
+
     def test_vue_tagname(self):
 
         # default
@@ -133,6 +159,66 @@ class TestGrid(WebTestCase):
         grid.set_action_urls(setting, setting, 0)
         self.assertEqual(setting['_action_url_view'], '/blarg')
 
+    def test_pageable(self):
+        grid = self.make_grid()
+        self.assertFalse(grid.paginated)
+        grid.pageable = True
+        self.assertTrue(grid.paginated)
+        grid.paginated = False
+        self.assertFalse(grid.pageable)
+
+    def test_get_pagesize_options(self):
+        grid = self.make_grid()
+
+        # default
+        options = grid.get_pagesize_options()
+        self.assertEqual(options, [5, 10, 20, 50, 100, 200])
+
+        # override default
+        options = grid.get_pagesize_options(default=[42])
+        self.assertEqual(options, [42])
+
+        # from legacy config
+        self.config.setdefault('tailbone.grid.pagesize_options', '1 2 3')
+        grid = self.make_grid()
+        options = grid.get_pagesize_options()
+        self.assertEqual(options, [1, 2, 3])
+
+        # from new config
+        self.config.setdefault('wuttaweb.grids.default_pagesize_options', '4, 5, 6')
+        grid = self.make_grid()
+        options = grid.get_pagesize_options()
+        self.assertEqual(options, [4, 5, 6])
+
+    def test_get_pagesize(self):
+        grid = self.make_grid()
+
+        # default
+        size = grid.get_pagesize()
+        self.assertEqual(size, 20)
+
+        # override default
+        size = grid.get_pagesize(default=42)
+        self.assertEqual(size, 42)
+
+        # override default options
+        self.config.setdefault('wuttaweb.grids.default_pagesize_options', '10 15 30')
+        grid = self.make_grid()
+        size = grid.get_pagesize()
+        self.assertEqual(size, 10)
+
+        # from legacy config
+        self.config.setdefault('tailbone.grid.default_pagesize', '12')
+        grid = self.make_grid()
+        size = grid.get_pagesize()
+        self.assertEqual(size, 12)
+
+        # from new config
+        self.config.setdefault('wuttaweb.grids.default_pagesize', '15')
+        grid = self.make_grid()
+        size = grid.get_pagesize()
+        self.assertEqual(size, 15)
+
     def test_render_vue_tag(self):
         model = self.app.model