Update CHANGELOG.txt with RT's added to 2.7.0.

CHANGELOG.txt

@@ -151,6 +151,7 @@ Attached RT's:
 798253: TDX report dates not displaying properly in WCMS (ebremner (Eric Bremner))
 798801: Single page: Event related error messages (kpaxman (Kevin Paxman))
 798895: icons in facts and figures missing alt text (at least on single page) (l26yan (Lily Yan))
+799125: Update Twitter widget for upcoming deprecations and removals, and make sure all current embeds are supported [resolved] (l26yan (Lily Yan))
 801078: Menu disappeared from WCMS publications site (tstruyk (Tyler Struyk))
 801285: WCMS Custom Coding for IAP's Tableau server generating error message (tstruyk (Tyler Struyk))
 801576: Update to elysia_cron 7.x-2.5 (lkmorlan (Liam Morland))
@@ -248,6 +249,7 @@ Attached RT's:
 892622: Fix gmap marker bundle error when clearing caches (kpaxman (Kevin Paxman))
 892643: Update to webform_validation 7.x-1.15-rc1 (lkmorlan (Liam Morland))
 897777: uw_ct_award is overridden (l26yan (Lily Yan))
+901941: Mailchimp Plugin Issue (kpaxman (Kevin Paxman))
 
 UW Base Profile 7.x-2.6.1
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