Merge branch '1358-message-bubbles' into 'master'

briar-android/build.gradle

briar-android/src/main/res/drawable-hdpi/msg_in.9.png

briar-android/src/main/res/drawable-hdpi/msg_in_top.9.png

briar-android/src/main/res/drawable-hdpi/msg_out.9.png

briar-android/src/main/res/drawable-hdpi/msg_out_top.9.png

briar-android/src/main/res/drawable-hdpi/notice_in.9.png

...android/src/main/res/drawable-hdpi/notice_in_bottom.9.png

briar-android/src/main/res/drawable-hdpi/notice_out.9.png

...ndroid/src/main/res/drawable-hdpi/notice_out_bottom.9.png

briar-android/src/main/res/drawable-mdpi/msg_in.9.png

briar-android/src/main/res/drawable-mdpi/msg_in_top.9.png

briar-android/src/main/res/drawable-mdpi/msg_out.9.png

briar-android/src/main/res/drawable-mdpi/msg_out_top.9.png

briar-android/src/main/res/drawable-mdpi/notice_in.9.png

...android/src/main/res/drawable-mdpi/notice_in_bottom.9.png

briar-android/src/main/res/drawable-mdpi/notice_out.9.png

...ndroid/src/main/res/drawable-mdpi/notice_out_bottom.9.png

briar-android/src/main/res/drawable-night-hdpi/msg_in.9.png

...android/src/main/res/drawable-night-hdpi/msg_in_top.9.png

briar-android/src/main/res/drawable-night-mdpi/msg_in.9.png