the filter() function can be chained between the accessor and the value
function to get a filtered value. When no filter allable is given in the
filter() function, stripctl() is used to strip all control chars (ASCII<32)

Examples:

  $INPUT->post->filter()->str('foobar');
  $INPUT->get->filter('myfilter')->int('baz');

this should test the correctness of the return value of is_ssl()
function based on various combinations of PHP environment variables

This avoids treating double slashes as single line comments in CSS when
they are used in a filter or content string.

closes #638

That commit did not test what it actually made for. Handling protocol
relative URLs in CSS.

This introduces an abstract base class that command line tools need to
inherit from. It provides a simple framework for registering accepted
command line options and provides commonly needed things like help
output and colored text.

Existing CLI scripts still need to be converted.

1. cachetime setting should only be applied to the cache_renderer
   class.  Previously it was applied to cache_parser (and by
   extension cache_handler).
2. two special cachetime values, -1 & 0, weren't handled, per
   FS#2183

To handle the cachetime setting, -1, disable caching, a new
property _nocache is added.  When that property is true, any cache
file must not be used and storecache() should not store any values

source maps are invalid for our dispatched sources and may even cause
problems. this makes sure any sourcemap declarations are stripped from
the output

This very basic test ensures that the useCache method works as
expected for simple scenarios. This test case fails without commit
a8795974 and then also triggers the
warning that was introduced in bc2ddb54

Mostly this is for unit tests which use of \$_SERVER['REMOTE_USER']

It ensures the reference/alias connection between \$INPUT->server
and \$_SERVER is renewed before each test.  Tests using TestRequest
class will replace this \$INPUT with their own.

double slashes in url() always have to be ignored

Added DOKU_BASE for local target

if a needed CONNECT tunnel fails

connections are now retried after timeout and failing connections will
be marked as skipped instead of failing. This should reduce false alarms
on travis