Changes

[lldb] Add a setting to not install the main executable
Summary: Add setting target.auto-install-main-executable that controls
whether the main executable should be automatically installed when
connected to a remote platform even if it does not have an explicit
install path specified. The default is true as the current behaviour.
Reviewers: omjavaid, JDevlieghere, srhines, labath, clayborg
Reviewed By: clayborg
Subscribers: kevin.brodsky, lldb-commits, llvm-commits
Tags: #lldb
Differential Revision: https://reviews.llvm.org/D71761