fix(tree) - Refactor out Recursive Tree Item into it's own component to resolve data issues

[smashleez]

This pull requests fixes a few things:

• Ability to configure disabled items from being displayed in the tree. In our implementations any items the user doesn't have access to comes back as disabled, which we were not supporting previously.
• Refactor to help track down data issues - instead of each recursive 'Tree' element having to maintain it's own data and fight with state, the parent component is the one that keeps track of the data and just feed it to a recursive TreeViewItem component.
• Fix visibility of 'Select All' and 'Expand All' text when filtering items.

[codecov[bot]]

Codecov Report

Merging #1271 (4ff305e) into master (936713b) will increase coverage by 14.71%. The diff coverage is 99.41%.

@@             Coverage Diff             @@
##           master    #1271       +/-   ##
===========================================
+ Coverage   84.53%   99.25%   +14.71%     
===========================================
  Files           9        2        -7     
  Lines         304      267       -37     
  Branches       70       91       +21     
===========================================
+ Hits          257      265        +8     
+ Misses         47        2       -45     

Impacted Files	Coverage Δ
packages/tree/src/Tree.tsx	99.17% <99.32%> (ø)
packages/tree/src/TreeItemContent.tsx	100.00% <100.00%> (ø)

... and 9 files with indirect coverage changes

Help us with your feedback. Take ten seconds to tell us how you rate us. Have a feature suggestion? Share it here.