Input box tweaks

[Blackbaud-PaulCrowder]

• Added support for a wrapping element around the sky-form-control element to support various composite scenarios such as autocomplete, phone field, etc.
• Use drop shadow instead of border for active/focus/hover states so padding does not have to be adjusted
• Added support for adding buttons to the left side of input box

[blackbaud-ado]

Preview build at https://host.nxt.blackbaud.com/skyux-forms?_sp.spa=pr-wrapper-support

[blackbaud-ado]

Preview build at https://host.nxt.blackbaud.com/skyux-forms?_sp.spa=pr-wrapper-support

[codecov]

Codecov Report

Merging #195 into master will not change coverage.
The diff coverage is 100.00%.

@@            Coverage Diff            @@
##            master      #195   +/-   ##
=========================================
  Coverage   100.00%   100.00%           
=========================================
  Files           29        29           
  Lines          864       865    +1     
  Branches       164       164           
=========================================
+ Hits           864       865    +1     

Impacted Files	Coverage Δ
...pp/public/modules/input-box/input-box.component.ts	100.00% <100.00%> (ø)

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[blackbaud-ado]

Preview build at https://host.nxt.blackbaud.com/skyux-forms?_sp.spa=pr-wrapper-support

[blackbaud-ado]

Preview build at https://host.nxt.blackbaud.com/skyux-forms?_sp.spa=pr-wrapper-support