Restructure and document retroshare.pri variables and helper functions
Link sqlite statically like other libraries on Android
qmake has multiple win32-* specs match them correctly
Move a buch of generic thing to retroshare.pri instead of having them replocated
accross project specific .pro
Fix retroshare-gui too many symbols exported on windows liking error by adding
QMAKE_LFLAGS+=-Wl,--exclude-libs,ALL
Rename retroshare-gui/src/util/win32.h because the name is too prone to
confusion and build conflicts
libreasapi avoid usage of cretar_prl link_prl that seems unreliable on some
platforms
libreasapi rename LIBRESAPI_QT to more understendable LIBRESAPI_SETTINGS
Use use_*.pri instead of copy pasting error prone qmake snippets around
Expose bitdht option to retroshare.pri
Add RS_THREAD_LIB qmake variable for better crossplatform support
Move debug and profiling generic options to retroshare.pri (avoid copy/pasting)
Remove Qt script module in qmake as it is not available anymore
In lastest Qt versions linux-* mkspec doesn't match android anymore,
this was triggering a compilation error as DATA_DIR was not defined the
RsAccountsDetail::PathDataDirectory(bool check) code has been rearranged
so it works reasonably also on Android and do not depend on DATA_DIR
define anymore
Updated Android compiling documentation
