fix Issue 10716 - Horrifically slow compilation for array literals inside functions
fix Issue 10736 - Regression (2.064 git-head): Instantiation failure triggered by module import and module order

In the reduced test case, `test10736b` instantiates `chunks` template
function, then it instantiates `Chunks!(int[])`. The instance object will
be inserted to `test10736a` member because it is the first module that
importing `test10736c`. But in this time, `test10736a` module's semantic3
is already done, then `Chunks!(int[])` would immediately invoke its
semantic3, then `Chunks!(int[]).opSlice` refers *not yet instantiation
finished* `chunks` template.

To avoid the forward reference problem, we should defer semantic3 of
template instances which inserted to module scope.
fix issue 10744 - Rejects valid interface inheritance + wrong error
message
fix Issue 10431 - ICE(DMD 2.063) in struct.c:741 (1)
Merge pull request #2451 from hpohl/10744

[REG2.064a] fix issue 10744 - Rejects valid interface inheritance + wrong error message
Merge pull request #2442 from 9rnsr/fix10736

[REG2.064a] fix Issue 10736 - Regression (2.064 git-head): Instantiation failure triggered by module import and module order
Fix issue 10388 - Compile DMD with Clang on Mac OS X.
fix issue 10783 - ICE and bad diagnostics when using non-existent
symbols in switch and with statements
Merge pull request #2457 from hpohl/10783

fix issue 10783 - ICE and bad diagnostics when using non-existent symbols in switch and with statements
fix issue 9247 - Compiler accepts opaque struct returned by value from
function pointer declaration.
Add Port::fequal for longdouble comparisons.
fix Issue 10726 - Bogus Circular Reference error if opEquals defined and has a loop

This is also the better fix for issue 10567.
Update 10567 test case for exhaustive check of TypeInfo generation
Merge pull request #2458 from hpohl/9247

fix issue 9247 - Compiler accepts opaque struct returned by value from function pointer declaration.
fix issue 10788 - forward reference of enum member E from another module
fix issue 10787 - static ~this attributes position
Merge pull request #2461 from ibuclaw/fequal

Add Port::fequal for longdouble comparisons.
fix Issue 4481 - ICE(glue.c,!vthis->csym) or compiles, depending on the import statements order
fix issue 10792 - Bad diagnostic on new eponymous enum template syntax
Merge pull request #2465 from hpohl/10792

fix issue 10792 - Bad diagnostic on new eponymous enum template syntax