webdav: lang::XMultiServiceFactory -> uno::XComponentContext

Change-Id: I71984066a512a023c67d1690bd984d66f75f894b
#i120041# Update of serf library from 1.0.0 to 1.1.0.

(cherry picked from commit eb0311f38de6c30fb15f87b4599e932897f281f5)

Conflicts:
	external_deps.lst
	scp2/source/ooo/file_library_ooo.scp
	solenv/bin/download_external_dependencies.pl
	ucb/source/ucp/webdav/SerfPostReqProcImpl.cxx
	ucb/source/ucp/webdav/SerfPropFindReqProcImpl.cxx
	ucb/source/ucp/webdav/SerfPropPatchReqProcImpl.cxx
	ucb/source/ucp/webdav/SerfPutReqProcImpl.cxx
	ucb/source/ucp/webdav/SerfSession.cxx

Change-Id: I6b9576226f86b87397bedc2b67a9289bc19317a7
minor WaE cleanup for SerfRequestProcessorImpl.hxx

that solves another dozen warnings
(cherry picked from commit f42f6eb8aa2ab01befeba42871d9d5c7b381f49f)

Change-Id: Ia06cee06e04b09fe6ed45cf4159722be191a21d2
 #122008# - use <serf_bucket_headers_setc(..)>

when header name's data need to be copied

(cherry picked from commit e50d4638e4fe64eb05b8f22006c7f04c05ec288b)

Change-Id: Ib4f171b05bafe380187a09cbfe143b0bef8b6f25
 #i123068# remove implicit conversions from rtl strings to their elements

(cherry picked from commit 1a15756db5173403fcdbc3ad522c3a76e88a7082)

Conflicts:
	ucb/source/ucp/webdav/DAVProperties.cxx
	ucb/source/ucp/webdav/SerfRequestProcessor.cxx
	ucb/source/ucp/webdav/SerfSession.cxx

Rest ignored.

Change-Id: I7d25170cc07538dbab70bc72af8764820da2b60b
webdav: fix cherry-pick commit 7056e8ef89e938e38fc5b2b8a7493f0c79d5efd4

Change-Id: I177daf0d4e22d96167ab094a5c9d5c9cab6cf409
webdav: std::hash_set|map -> std::unordered_set|map

Change-Id: Id0c18cb51af742d073d532662558fdd84d476f88
webdav: fix include paths

Change-Id: I323bef2e1c21e2a1981409d4295ccf555088e5ea
webdav: fix remaining build issues

Change-Id: I9416551ba78a6a27071fdf92a6c36c271a1032b7