xcode: use a map to look up target pointers

Rather than iterating over a vector, use a map to associate targets with
XCode objects.
Merge topic 'xcode-target-search-perf' into next

20bff460 xcode: use a map to look up target pointers
test: test source file properties with case-insensitivity

Some filesystems are case insensitive, so when setting properties on the
files, this should be respected (modulo a policy decision).
Merge topic 'icase-source-file-prop' into next

6c9d3356 test: test source file properties with case-insensitivity
CMakeParseImplicitLinkInfo: Fix implicit library logging

In commit v3.1.0-rc1~640^2~5 (Clean up usage of if(... MATCHES regex)
followed string(REGEX REPLACE regex), 2014-04-06) we accidentally broke
logging of the implicit library detection.  Restore use of the
intermediate 'lib' variable so that the log message is constructed
properly.

Reported-by: Bill Somerville <bill@classdesign.com>
Merge topic 'fix-implicit-lib-logging' into next

20bf6971 CMakeParseImplicitLinkInfo: Fix implicit library logging