Refactor dotest/debugserver env variables for simplicity

Hi Greg/all,

Currently, I have to define a lot of different environment variables to get all of the logs I typically need/want. Are you okay with the proposed change?

CURRENT WAY

dotest.py
export LLDB_LOG=/tmp/basename-lldb.log
export LLDB_LOG_OPTION=all
export GDB_REMOTE_LOG=/tmp/basename-gdb-remote.log
export GDB_REMOTE_LOG_OPTION=all

debugserver
export LLDB_DEBUGSERVER_LOG_FILE=/tmp/basename-lldb-server-gdb-remote.log
export LLDB_DEBUGSERVER_LOG_FLAGS=all
export LLDB_DEBUGSERVER_EXTRA_ARG_1=“-c”
export LLDB_DEBUGSERVER_EXTRA_ARG_2=“log enable -Tpn -f /tmp/basename-lldb-server-lldb.log lldb all”

PROPOSED WAY (generates all of the files shown above)

export LLDB_LOG=/tmp/basename
export LLDB_LOG_OPTION=“lldb all;gdb-remote all”

This will also help us break the dependency between lldb-sever and the command line interpreter.

Also, currently, it isn’t possible to get meaningful logs from dosep.py because the different dotest invocations stomp on each other. I’m planning on using this change to make it easier to direct the various log files into test specific log files.

I’m starting to think that

export LLDB_LOG=/tmp/basename

isn’t even necessary. Just use the test session dir.

It is still good to have the ability to specify a file.

I don't really care how we specify the log, just don't change "debugserver". You can change detest.py and lldb-server, but why not just use options to dotest.py instead of environment variables?