Adds rollup-rfc to docs

[dbbaughe]

Issue #, if available:

Description of changes:

By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.

[codecov]

Codecov Report

Merging #248 into master will decrease coverage by 0.10%.
The diff coverage is n/a.

@@             Coverage Diff              @@
##             master     #248      +/-   ##
============================================
- Coverage     71.67%   71.56%   -0.11%     
  Complexity      633      633              
============================================
  Files            86       86              
  Lines          3647     3647              
  Branches        601      601              
============================================
- Hits           2614     2610       -4     
- Misses          722      726       +4     
  Partials        311      311              

Impacted Files	Coverage Δ	Complexity Δ
...ement/step/notification/AttemptNotificationStep.kt	62.06% <0.00%> (-20.69%)	5.00% <0.00%> (ø%)
...ticsearch/indexstatemanagement/model/Transition.kt	80.39% <0.00%> (-1.97%)	5.00% <0.00%> (ø%)
...ndexstatemanagement/IndexStateManagementIndices.kt	66.66% <0.00%> (+6.24%)	10.00% <0.00%> (ø%)

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[dbbaughe]

Codecov failure because of testing randomization, unrelated to PR.