Checking for overflow should be done before integer overflows.
There are two checks:
(result > limit / base) is used for limits greater than rounded up to base,
e.g. for 65535 it will activate for 65540 and higher.
(result * base > limit - digit) is used for limit+1 to limit+n below
next base rounded number, e.g. 65536 up to 65539.
* Fixes#240: Multiple long option names / aliases
* We now use a vector of long option names instead of a single name
* When specifying an option, you can provide multiple names separated by commas, at most one of which may have a length of 1 (not necessarily the first specified name). The length-1 name is the single-hyphen switch (the "short name").
* Hashing uses the first long name
* Option help currently only uses the first long name.
* Fixes#345, fixes#346, regards #340: Put exceptions in a sub-namespace and renamed them accordingly.
* Also fixed some "loose ends" regarding namespace indentation which were missing in PR #350.
* Dropped `required_option_missing` as it is unused.
* Namespace no longer induce indentation
* Namespace opening brace now on same line as namespace name
* Namespace closing brace now has an empty line before it unless the namespace contents were short and with no empty lines
* Namespace closing brace now always followed by a comment with the closed namespace' name
* -Wsuggest-override is not supported by gcc before 5.0
* GCC prior to 5.0 should ignore not only -Wnon-virtual-dtor but also -Weffc++, otherwise non-virtual destructor problems will still be reported.
* The `#pragma GCC diagnostic push' should be used before setting up the temporary environment.
* When using GCC4.8, use manual lexical analysis instead of regular expressions.
* Add gcc4.8 stuff to travis file.
* -Wsuggest-override is not supported by gcc before 5.0
* GCC prior to 5.0 should ignore not only -Wnon-virtual-dtor but also -Weffc++, otherwise non-virtual destructor problems will still be reported.
* The `#pragma GCC diagnostic push' should be used before setting up the temporary environment.
