Add option to configure bin target directory

Define a new toolchain option “bindir” use it in “Makefile.in”.

The new “Configure.pl” “bindir” option control the install path for the
executable files.  The default is “@prefix@/bin/”.
Add option to configure lib target directory

The build system does not permit to configure the lib target directoriy,
this is required for Debian packaging with multi-arch support[1].

The new “Configure.pl” “libdir” option control the install path for the
library.  The default is “@prefix@/lib/” on POSIX toolchain and
“@bindir@” on MSVC.

The new “libdir” replace both the “shareddir” and “staticdir” options.

Footnotes:
[1]  https://www.debian.org/doc/manuals/maint-guide/advanced.en.html#multiarch
Add option to configure MAST target directory

The architecture independent MAST files were installed under
“@prefix@/lib/” and the build system does not permit to configure it.

The new “Configure.pl” “mastdir” option control the install path for the
MAST files.  The default is “@prefix@/share/nqp/lib” on all toolchains.
Generate a pkg-config metafile

This metafile will permit nqp to retrieve the path of MAST files with:

    pkg-config --variable=mastdir moar
Remove generated pkg-config files on distclean
Convert the pkg-config generator to perl

Perl is required for the build system, using it to generate the
pkg-config metafile can not fail.
Fix the match on libdir

By default “$libdir” is “/usr/lib”, requiring a trailing “/” makes the
match fail.
Strip double quotes in moar.pc

The .pc file is not a shell script, the double quote are useless and
require extra handling for users.
Merge branch 'master'

Conflicts:
	Configure.pl
	build/Makefile.in
Merge branch 'master' into feature/parameterized-target-directories

Conflicts:
	Configure.pl
	build/Makefile.in
Remove slash between $(DESTDIR) and the target

This make wrong paths under windows:

C:\Perl64\bin\perl.exe -MExtUtils::Command -e mkpath /C:\nqp\install\bin
Use q-string to avoid interpolation

On windows “C:\nqp\install” is interpolated as:

    C:
    qpinstall

with warning about “Unrecognized escape \i passed through”.
Merge pull request #113 from baby-gnu/feature/parameterized-target-directories

Feature/parameterized target directories