feat(datepicker): export calendar with time component

[yggg]

Please read and mark the following check list before creating a pull request:

• I read and followed the CONTRIBUTING.md guide.
• I read and followed the New Feature Checklist guide.

Short description of what this resolves:

Closes #2524. And small timepicker docs fix (Closes #2526).

[codecov]

Codecov Report

Merging #2528 into master will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master    #2528   +/-   ##
=======================================
  Coverage   78.93%   78.93%           
=======================================
  Files         253      253           
  Lines        7808     7808           
  Branches      855      855           
=======================================
  Hits         6163     6163           
  Misses       1380     1380           
  Partials      265      265           

Impacted Files	Coverage Δ
...k/theme/components/datepicker/datepicker.module.ts	100.00% <ø> (ø)
...heme/components/timepicker/timepicker.directive.ts	22.95% <ø> (ø)