This removes the implementation of the `swift-indent` tool, its
associated documentation, and utilities. This tool was never completed
and has much better alternatives with `swift-format` which is more
flexible and actually maintained.
* Fix unnecessary one-time recompile of stdlib with -enable-ossa-flag
This includes a bit in the module format to represent if the module was
compiled with -enable-ossa-modules flag. When compiling a client module
with -enable-ossa-modules flag, all dependent modules are checked for this bit,
if not on, recompilation is triggered with -enable-ossa-modules.
* Updated tests
