Update the readme links to be absolute github links

[adithyaov]

Broken links in streamly-examples-0.1.3/README.html

• examples/Intro.hs
• examples/MergeSort.hs
• examples/Rate.hs
• examples/CoreUtils.hs
• examples/CoreUtilsHandle.hs
• examples/Split.hs
• examples/FileSystemEvent.hs
• examples/ListDir.hs
• examples/CamelCase.hs
• examples/WordCount.hs
• examples/WordCount.c
• examples/WordCountModular.hs
• examples/WordCountParallel.hs
• examples/WordCountParallelUTF8.hs
• examples/WordFrequency.hs
• examples/CSVParser.hs
• examples/EchoServer.hs
• examples/MergeServer.hs
• examples/FileSender.hs
• examples/CmdServer.hs
• examples/CmdClient.hs
• examples/WordServer.hs
• examples/AcidRain.hs
• examples/CirclingSquare.hs
• examples/ControlFlow.hs
• examples/Interop/Streaming.hs
• examples/Interop/Pipes.hs
• examples/Interop/Conduit.hs
• examples/Interop/Vector.hs
• LICENSE

[harendra-kumar]

Updated to absolute links but they point to master branch. Ideally we need them to point to a particular release.