Move some Host logic into HostInfo class.

This patch creates a HostInfo class, a static class used to answer
basic queries about the host platform.  As part of this change,
some functionality is moved from Host to HostInfo, and relevant
fixups are performed in the rest of the codebase.

This is part of a larger effort to isolate more code in the Host
layer into platform-specific groups, to make it easier to make
platform specific changes for a particular Host without breaking
other hosts.

Reviewed by: Greg Clayton

Differential Revision: http://reviews.llvm.org/D4963

git-svn-id: https://llvm.org/svn/llvm-project/lldb/trunk@215992 91177308-0d34-0410-b5e6-96231b3b80d8
Fix .clang-format file to adhere to LLDB 140 column limit.

git-svn-id: https://llvm.org/svn/llvm-project/lldb/trunk@215993 91177308-0d34-0410-b5e6-96231b3b80d8
Adjust process launch --disable-aslr to take true/false value.

This change modifies the 'process launch' --disable-aslr option to take a boolean argument.  If the user directly specifies --disable-aslr {true,false}, that setting will control whether the process is launched with ASLR disabled accordingly.  In the event that the setting is not explicitly made on the process launch command line, then the value is retrieved from the target.disable-aslr setting (i.e. settings show target.disable-aslr).


git-svn-id: https://llvm.org/svn/llvm-project/lldb/trunk@215996 91177308-0d34-0410-b5e6-96231b3b80d8