gui: PatternPassword: allow any N*N grid

Rather than only supporting a 3x3 grid, allow for multiple grid sizes
(using the CyanogenMod method of generating passphrases for non-3x3
grids). Also fix the detection of touches, as the old code was far too
sensitive for larger grids (and also didn't make much sense).

Change-Id: I343ef654e6d29ce0cb790a28281be7c7c9b171d9
Signed-off-by: Aleksa Sarai <cyphar@cyphar.com>
diff --git a/gui/theme/common/languages/en.xml b/gui/theme/common/languages/en.xml
index 2847d22..e417ace 100755
--- a/gui/theme/common/languages/en.xml
+++ b/gui/theme/common/languages/en.xml
@@ -435,6 +435,7 @@
 		<string name="decrypt_data_hdr">Decrypt Data</string>
 		<string name="decrypt_data_enter_pass"></string>
 		<string name="decryt_data_failed">Password failed, please try again!</string>
+		<string name="decryt_data_failed_pattern">Pattern failed, please try again!</string>
 		<string name="decrypt_data_enter_pattern">Enter Pattern.</string>
 		<string name="decrypt_data_trying">Trying Decryption</string>
 		<string name="term_hdr">Terminal Command</string>