Compare buffer names in both lowercase and uppercase

This appears to have the most liberal behaviour in both German and
Turkish.

Fixes issue #140.
Merge pull request #142 from lp0/fix-buffer-filter

Compare buffer names in both lowercase and uppercase
Use eu.lp0.slf4j:slf4j-android
Revert "FIX #85"

This reverts commit 5a0b8f40f1762d74428a1aa9c554a503e0d14098.
Add TCP keepalive
Make keepalive configurable

This doesn't include realtime updates to the current connection,
although that would be possible.