Replace index:eselect() with index:select()

src/box/lua/box_net.lua

src/box/lua/schema.lua

test/big/lua.result

test/big/lua.test.lua

test/big/sql.result

test/big/sql.test.py

test/big/tree_pk.result

test/big/tree_pk.test.lua

test/box/admin.result

test/box/net.box.result

test/box/net.box.test.lua

test/box/select.result

test/box/select.test.lua

test/box/stat.result