[Fift > Types] Missing crosslinks

[jeshecdom]

Add links at following places, once page for Basic values (#1468) is merged into main:

• Tuples section and top level link to basic values page:

  • Refer to the Tuples section in the basic values page.

Add links at following places, once page for Control flow (#1541) is merged into main:

• Blocks section and top level link to control flow page:

  • See section for Blocks in the Control Flow page

Add links at following places once Fift hashmaps section is added to Basic values page (see issue #1635).

• Fift hashmaps section and top level to basic value page.

  • Refer to Fift hashmaps section in the Basic Values page.