Adjust the values of dirs1 and dirs2 so that rotate_and_place orients textures correctly

According to doc/lua_api.txt if paramtype2 == "facedir" the two least significant bits of parm2 orient the texture around the axis. For dirs1 (looking at a wall) these would be 0, 1, 2, 3 and for dirs2 (looking at the ceiling) 2, 1, 0, 3
Fixes for Android build errors. Enable sensor landscape rotation.

Fix typo in Android Makefile ndk path.
Fix touchscreen parts of game.cpp to work after Zeno's refactor.
Fix isdigit and isspace overload conflict with Android Irrlicht in string.h
Enable sensor landscape rotation in Android Manifiest.
Add mapgen v5 to Android build.
Fix Makefile not checking leveldb.

Signed-off-by: Craig Robbins <kde.psych@gmail.com>
Fix client "double saving" simple singleplayer local maps
Increase step smoothing to fit 1:1 stairs (works well on slabs too)

Signed-off-by: Craig Robbins <kde.psych@gmail.com>
Fix Android main menu crash, and user data directory check.

Signed-off-by: Craig Robbins <kde.psych@gmail.com>
Only set the camera update keymap when using a debug build

Signed-off-by: Craig Robbins <kde.psych@gmail.com>
Fix some undeclared global variables
Wieldmesh: don't force anisotropic filtering on, instead disable mipmaps

This should fix #1844. Thanks to oleastre for making the first version
of this commit (#1848).
added enable_build_where_you_stand option

Signed-off-by: Craig Robbins <kde.psych@gmail.com>
EMF_USE_MIP_MAPS was introduced in Irrlicht 1.8, don't use in 1.7.3 or below

This is not optimal as it will cause minor graphical glitches for
Irrlicht 1.7 users, but at least it fixes the build.
Wield: always obey anisotropic_filter setting, not just for hi res textures
Don't corrupt stepheight when setting other properties
Add minetest.copy_table(table) To get rid off the "table references"

Signed-off-by: Craig Robbins <kde.psych@gmail.com>
Fix regression with command line --go option
Update minetest.po (Japanese)
Improve Lua API documentation

Changes:
  * Add extra documentation for remove_item.

    This isn't as silly as it sounds: iterate a list containing items with
    unique metadata each, and remove_item the first one you find, placing
    into a different - fine, except the remove will invariably remove the
    wrong one, leading to items being duplicated and others destroyed.

    Arguably it's a bug, and Inventory::removeItem should actually remove
    the item you tell it to. (i.e. if the passed ItemStack has metadata,
    match it). But it seems reasonable to just document the behaviour
    more clearly.

 * Improve string_to_pos documentation.
 * Clarify dig_node documentation (return value).
 * Better on_step documentation.
 * get_nodemeta -> get_meta.
 * Other minor fixes.
Fix MSVC compiling error (argc/argv not available to pass to init_gettext)

Signed-off-by: Craig Robbins <kde.psych@gmail.com>