Add a test case where 'settings set frame-format' supplies a format string containing, among other things, a single backtick character.
Add a test case where 'settings set frame-format' supplies a format string containing, among other things, a single backtick character.

rdar://problem/10712130


git-svn-id: 4c4cc70b1ef44ba2b7963015e681894188cea27e@148403 91177308-0d34-0410-b5e6-96231b3b80d8

llvm-mirror/lldb,apple/swift-lldb,llvm-mirror/lldb,apple/swift-lldb,apple/swift-lldb,llvm-mirror/lldb,apple/swift-lldb,llvm-mirror/lldb,llvm-mirror/lldb,apple/swift-lldb,apple/swift-lldb