Fix some warnings on !MONO_ARCH_AOT_SUPPORTED targets.
[System] WebConnection and WebConnectionStream code cleanups.

* Merged WebConnection.EndWrite() and EndWrite2().

* WebConnectionStream.BeginWrite(): Use the same async-write
  callback for both chunked and non-chunked; remove the single-use
  small WriteRequestAsync() and inline it here to make the code
  more readable.

* WebConnectionStream.WriteRequestAsyncCB(): Now called for all
  async writes, call WebConnection.EndWrite() here.

The code is now more readable and easier to understand.  This is
the first part of a series of cleanups, which should eventually
lead towards full async and 100-continue.
Fixed time outs on http redirects

Fixed bug introduced by change 6ab86f50fd944b770ca388b478ce3cfb8b065647
where http request times out when it encounters a redirect.
[System] Add new NET_4_5 values for SslProtocols enum
[SSL/TLS] Add support to select and/or re-order ciphers suites [#16327]
[SSL/TLS] Expose Client/Server callbacks that can be used to select/reorder SSL/TLS cipher suites used (for client or server) and add unit tests for them [#16327]
[SSL/TLS] Update tlstest tool to build with 4.5 and to use/filter the client cipher suites
Merge pull request #905 from AxlPr/master

Fixed time out on HTTP redirects
[System.Net.Http] Return ContentLength of the buffer when content is loaded into a buffer in request handler. Fixes #17861
[SSL/TLS] Fix typo to build when INSIDE_SYSTEM is defined
Bug 17838 - IDictionary item property implemention for ConcurrentDictionary/SortedList_T  throws exception on non-existing key
Avoid double lookup for Dictionary IDictionary.get_Item property impl
Merge pull request #903 from simonhartmann/master

Bug 17838 - IDictionary item property implemention for ConcurrentDiction...
[System] Kill some Uri static fields
Add failing Uri test
[jit] Fix the stack cleanup during EH on x86 when LLVM is enabled.
Bump version.
[bcl] Fix test suites.
mono-api-html: support ignoring added members

Use Mono.Options as well.
mono-api-html: ignore members using regex, add detailed help
[jit] Fix a crash when using -v -v -v -v with dynamic methods.