Add asserts to check int values that was read with fread

[ZaWertun]

For example:

parcellite/src/preferences.c

Line 751 in c92cb98

if (1 != fread(name, size, 1, actions_file)){

parcellite/src/preferences.c

Line 756 in c92cb98

if (1 != fread(&size, 4, 1, actions_file)){

parcellite/src/preferences.c

Line 762 in c92cb98

if(1 != fread(command, size, 1, actions_file)){

parcellite/src/preferences.c

Line 767 in c92cb98

if (1 != fread(&size, 4, 1, actions_file)){

And others.