MAINT-5507: Remove HTTPClient and related cruft.

indra/llmessage/CMakeLists.txt

indra/llmessage/llcorehttputil.cpp

indra/llmessage/llcorehttputil.h

indra/llmessage/llexperiencecache.cpp

indra/llmessage/llhttpclient.cpp

indra/llmessage/llhttpclient.h

indra/llmessage/llhttpclientinterface.h

indra/llmessage/message.cpp

indra/newview/CMakeLists.txt

indra/newview/llaisapi.cpp

indra/newview/llaisapi.h

indra/newview/llappviewer.cpp

indra/newview/lleventpoll.h

indra/newview/llfloaterexperienceprofile.cpp

indra/newview/llfloaterexperiences.cpp

indra/newview/llgroupmgr.cpp

indra/newview/llmarketplacefunctions.cpp

indra/newview/llmeshrepository.h

indra/newview/llpanelexperiencepicker.cpp

indra/newview/llpanelgroupexperiences.cpp