Carefully widen pointers in wide_fill to avoid warnings about conversions between differently aligned types on ARM.
Attempt to workaround warnings of the form "narrowing conversion of 'foo' from 'int' to 'unsigned int' inside { } is ill-formed in C++11 [-Werror=narrowing]"
Don't run the custom_temporary_allocation examples for gcc < 4.4

Fixes #342
Merge pull request #346 from jaredhoberock/fix_small_warnings

Fix small warnings