mv columns and text align options to 'Layout' panel
update ignore file
make Android target
update luajit-launcher
fix blitbuffer to string of extra one byte copying
add reflowing benchmark
add cache spec
no need of luagettext module
add missing sample pdf for testing
update koreader-base
add travis CI for koreader
partial refresh when switching config panel
fix test frontend in travis
Merge pull request #597 from chrox/master

make Android target