- The output file name of the `rcc` command get computed once
in the AUTOGEN initializer and is passed in the info file.
- The function name for the `-name` option of `rcc` gets computed
once in the AUTOGEN initializer and is passed along with the
other `rcc` options in the info file.
This is a large commit that serves multiple purposes
- Iterate source files only once and store all extracted
information in a cmQtAutogenDigest class that can be reused.
This is brings speed improvements because several properties
are only evaluated once. More that that it helps to avoid
duplication of code with non trivial files property checks.
- Fix the Visual Studio generator to use PRE_BUILD when possible.
- Convert `for( ... )` loops to C++11 range base loops where possible
(cmQtAutogen*.cxx only).
- String concatenation optimizations.
