Various bug fixes and small features (#606)

* Fix stray cursor, integer overflows and other bugs

* check for getenvlist error, shorten code

* fix cascade, set info_line before auth, make code clearer and a bug fix

* Add option to turn on numlock at startup

* Fix setting numlock

* Update build.zig

* Custom info text

* Shift+Tab for previous input

* update changelog and res/config

* Some fixes

* update build.zig

* update build.zig again

* Fix xauth command for some shells and fix building in ReleaseSafe

* Use git describe to get dev version str

* revert change to getLockState (it broke the doom animation)

* add new ly error messages. Only try to make path for pam/exe during install when dest_directory is defined + print warning on error.

* add warning message for workaround

res/lang/en.ini

@@ -1,3 +1,4 @@
+authenticating = authenticating...
 capslock = capslock
 err_alloc = failed memory allocation
 err_bounds = out-of-bounds index
@@ -5,7 +6,9 @@ err_chdir = failed to open home folder
 err_console_dev = failed to access console
 err_dgn_oob = log message
 err_domain = invalid domain
+err_envlist = failed to get envlist
 err_hostname = failed to get hostname
+err_mcookie = mcookie command failed
 err_mlock = failed to lock password memory
 err_null = null pointer
 err_pam = pam transaction failed
@@ -33,6 +36,8 @@ err_unknown = an unknown error occurred
 err_user_gid = failed to set user GID
 err_user_init = failed to initialize user
 err_user_uid = failed to set user UID
+err_xauth = xauth command failed
+err_xcb_conn = xcb connection failed
 err_xsessions_dir = failed to find sessions folder
 err_xsessions_open = failed to open sessions folder
 insert = insert