[MWF] Partially implement Help.ShowHelp
File URI's without a host are not UNC paths on Windows.

NUnit breaks when these URI's are treated as UNC paths, so I have no way of
running the tests on Windows without this change to see if it broke anything.
Not all URI tests pass, but the ones that fail seem unrelated to my change.

On Unix, the tests all work, but of course on Unix this is a no-op.

This commit licensed as MIT/X11.
[System.Core/Android] Update TimeZone database self test.

Add Makefile rules to automagically download the TimeZone database
from the Android target $(ADB_TARGET), and build the tzi.exe app.

	$ make android-dump-tzdata ADB_TARGET=-d
	# downloads timezone data into ./android/tzdb.
	# dumps timezone data into ./android/tzdata
	# builds ./tzi.exe

	# Show adjustment rules for a given timezone dump
	$ mono tzi.exe -i=tzdata/Asia/Amman

Add `tzi.exe -R` option to show the TimeZoneInfo.GetAdjustmentRules()
output for all encountered timezones.

Add `tzi.exe -o=PATH` option to dump the TimeZone data to disk for
interrogation.

Add `tzi.exe -i=PATH` option to read in the specified TimeZone data
file and dump the rules contained therein.

Update usage comments.
Revert this patch, as it broke the test suite
[Mono.Data.Tds] Allow sending of text data longer than 4000 characters by using a different column type. Fixes #21172.
Re-apply the patch, there isa  fix for it
Revert incorrect changes from commit 950d9c8a567273c3363f43cee454f2b95a9f5da7

Correctly handle null value deserialization in non-generic Deserialize(string, Type) method.
[sgen] Don't loop endlessly when out of memory.
[sgen] Fix crash in late pinning.

Our code assumed that late-pinned objects don't have a tag, but they
obviously have the pin tag, so use the safe function.
[sgen] Don't store pin queue addresses, only indexes.  Fixes #24084.

The pin queue can get relocated as a side-effect of resizing when late
pinning happens, so we can't count on pointers into it to remain valid.
Add files that were forgotten in 6af798962810054fcf68f8e597de56b6490271a2, which is the re-apply of 950d9c8a567273c3363f43cee454f2b95a9f5da7
[llvm] Remove the unused LLVM_MAJOR_VERSION/LLVM_MINOR_VERSION defines.
Add the -Qunused-arguments warning to CPPFLAGS too.
Fix a warning.
[aot] Use the info->tramp_page_code_offsets array on arm as well.
[aot] Remove some obsolete TODOs.
Merge pull request #1381 from schani/fix-23401

Fix 23401
[runtime] Fix the android build with ndk r10c.
[sgen] Add an explanatory comment about OOM.
Merge pull request #1360 from madewokherd/winuncpath

File URI's without a host are not UNC paths on Windows.