HHVM 3.27.2

HHVM 3.27.2 is released! This release contains several bugfixes:

• Fix various crashes on MacOS due to differing assembler conventions
• Fix deadlock when calling HH\facts_parse in multiple simultaneous requests
• Fix conditional breakpoints in debugger
• Fix hang in debugger shutdown
• Fix IDE symbol search for namespaced symbols that start with a lowercase letter; this usually means namespaced functions.
• Fix hh_client crash on shutdown in some situations
• Fix crash when an unsupported experimental feature was enabled