fix #1083
fix #1070 by associating conentwidth zoom mode to auto cropping
add option to disable highlighting as well as dictionary lookup
This should also fix #973.
fix #968 by check the nullity of text range
add option to turn off e-ink optimization
which currently just sets free the limitation of panning gestures
emitting rate. This should fix #1039 when unchecking the
"E-ink optimization" in the "Screen settings".
add 'Home' key event to close filemanager
allow closing non-existent widget but throw a warning
Merge pull request #1085 from chrox/fix_1083

fix #1083
add user defined event map
This should fix #1016.

Usage for #1016:
Create a file named "custom.event.map.lua" in the koreader directory
with the following content:

return {
    [102] = "LPgFwd",
}
load Device module after DEBUG is turned on
otherwise some DEBUGs are not printed.
Merge pull request #1086 from chrox/fix_1070

fix #1070 by associating conentwidth zoom mode to auto cropping
Merge pull request #1087 from chrox/fix_973

add option to disable highlighting as well as dictionary lookup
Merge pull request #1088 from chrox/fix_968

fix #968 by check the nullity of text range
Merge pull request #1089 from chrox/fix_1039

add option to turn off e-ink optimization
Merge pull request #1091 from chrox/fix_1016

add user defined event map
Fix Kobo resume in new hardware abstraction.
Merge pull request #1093 from Frenzie/master

Fix Kobo resume in new hardware abstraction.
Implement UIManager:unschedule(action). Fixes #1007.
Merge pull request #1090 from chrox/fix_869

fix #869
Merge pull request #1097 from Frenzie/master

Implement UIManager:unschedule(action). Fixes #1007.